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How to write a PhD thesis: a step-by-step guide

A draft isn’t a perfect, finished product; it is your opportunity to start getting words down on paper, writes Kelly Louise Preece

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Kelly Louise Preece

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Congratulations; you’ve finished your research! Time to write your PhD thesis. This resource will take you through an eight-step plan for drafting your chapters and your thesis as a whole. 

Infographic with steps on how to draft your PhD thesis

Organise your material

Before you start, it’s important to get organised. Take a step back and look at the data you have, then reorganise your research. Which parts of it are central to your thesis and which bits need putting to one side? Label and organise everything using logical folders – make it easy for yourself! Academic and blogger Pat Thomson calls this  “Clean up to get clearer” . Thomson suggests these questions to ask yourself before you start writing:

  • What data do you have? You might find it useful to write out a list of types of data (your supervisor will find this list useful too.) This list is also an audit document that can go in your thesis. Do you have any for the “cutting room floor”? Take a deep breath and put it in a separate non-thesis file. You can easily retrieve it if it turns out you need it.
  • What do you have already written? What chunks of material have you written so far that could form the basis of pieces of the thesis text? They will most likely need to be revised but they are useful starting points. Do you have any holding text? That is material you already know has to be rewritten but contains information that will be the basis of a new piece of text.
  • What have you read and what do you still need to read? Are there new texts that you need to consult now after your analysis? What readings can you now put to one side, knowing that they aren’t useful for this thesis – although they might be useful at another time?
  • What goes with what? Can you create chunks or themes of materials that are going to form the basis of some chunks of your text, perhaps even chapters?

Once you have assessed and sorted what you have collected and generated you will be in much better shape to approach the big task of composing the dissertation. 

Decide on a key message

A key message is a summary of new information communicated in your thesis. You should have started to map this out already in the section on argument and contribution – an overarching argument with building blocks that you will flesh out in individual chapters.

You have already mapped your argument visually, now you need to begin writing it in prose. Following another of Pat Thomson’s exercises, write a “tiny text” thesis abstract. This doesn’t have to be elegant, or indeed the finished product, but it will help you articulate the argument you want your thesis to make. You create a tiny text using a five-paragraph structure:

  • The first sentence addresses the broad context. This locates the study in a policy, practice or research field.
  • The second sentence establishes a problem related to the broad context you have set out. It often starts with “But”, “Yet” or “However”.
  • The third sentence says what specific research has been done. This often starts with “This research” or “I report…”
  • The fourth sentence reports the results. Don’t try to be too tricky here, just start with something like: “This study shows,” or “Analysis of the data suggests that…”
  • The fifth and final sentence addresses the “So What?” question and makes clear the claim to contribution.

Here’s an example that Thomson provides:

Secondary school arts are in trouble, as the fall in enrolments in arts subjects dramatically attests. However, there is patchy evidence about the benefits of studying arts subjects at school and this makes it hard to argue why the drop in arts enrolments matters. This thesis reports on research which attempts to provide some answers to this problem – a longitudinal study which followed two groups of senior secondary students, one group enrolled in arts subjects and the other not, for three years. The results of the study demonstrate the benefits of young people’s engagement in arts activities, both in and out of school, as well as the connections between the two. The study not only adds to what is known about the benefits of both formal and informal arts education but also provides robust evidence for policymakers and practitioners arguing for the benefits of the arts. You can  find out more about tiny texts and thesis abstracts on Thomson’s blog.

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Write a plan

You might not be a planner when it comes to writing. You might prefer to sit, type and think through ideas as you go. That’s OK. Everybody works differently. But one of the benefits of planning your writing is that your plan can help you when you get stuck. It can help with writer’s block (more on this shortly!) but also maintain clarity of intention and purpose in your writing.

You can do this by creating a  thesis skeleton or storyboard , planning the order of your chapters, thinking of potential titles (which may change at a later stage), noting down what each chapter/section will cover and considering how many words you will dedicate to each chapter (make sure the total doesn’t exceed the maximum word limit allowed).

Use your plan to help prompt your writing when you get stuck and to develop clarity in your writing.

Some starting points include:

  • This chapter will argue that…
  • This section illustrates that…
  • This paragraph provides evidence that…

Of course, we wish it werethat easy. But you need to approach your first draft as exactly that: a draft. It isn’t a perfect, finished product; it is your opportunity to start getting words down on paper. Start with whichever chapter you feel you want to write first; you don’t necessarily have to write the introduction first. Depending on your research, you may find it easier to begin with your empirical/data chapters.

Vitae advocates for the “three draft approach” to help with this and to stop you from focusing on finding exactly the right word or transition as part of your first draft.

Infographic of the three draft approach

This resource originally appeared on Researcher Development .

Kelly Louse Preece is head of educator development at the University of Exeter.

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How Many References in a Research Paper?

how many references should a phd thesis have

Junior researchers frequently wonder how many references should be included in their research papers. The common response? “As many as you need.” What exactly does that mean? While we admit there are very few hard-set rules regarding this issue, in this article, we will try to provide more concrete guidelines that will help you assess whether you have enough references in your paper.

Before we do so, let us briefly explain why references matter and whether the number of references you include can project certain perceptions about the quality of your work. There is such a thing as having too many or too few.

Why are research paper references and citations necessary?

References show that you have carefully reviewed the relevant literature and are now contributing something  novel  to the academic community. You establish authority and credibility when you can critically assess other literature and distinguish your findings from previous works (if any exist). We emphasize “critically assess” in the last sentence because references are only as good as you apply them to your research. Therefore, the famous adage “quality over quantity” is the key to deciding how many references are sufficient.

Likewise, citing your references within the research paper itself (in the form of academic citations ) is crucial in any academic work that makes assertations based on external studies. Failing to cite your sources can result in plagiarism, which even if accidental can still have some devastating consequences for academic researchers hoping to publish their work or finish graduate school.

Number of Sources Used Can Impact Perceptions of Quality

We would be remiss if we didn’t tell you that being at either extreme (having too few or too many references) can reflect poorly on your intellectual aptitude and your study’s validity. Here’s why:

  • If you don’t have enough references, particularly on a topic familiar to a wide audience, readers may think that you haven’t done enough research into existing literature. Surely someone else has thought about related topics or used similar techniques. If you’re sloppy in conducting your diligence, readers will wonder whether your paper is worth reading. What’s novel and valuable about your paper? Were you just as sloppy with conducting your study? The answers to these questions need to be evident.
  • Additionally, readers might be concerned that you may have plagiarized by failing to properly cite information. Unless you’re John Nash, who cited only two texts in his seminal  26-page PhD thesis  (one of which was to his prior work), ensure that you’ve properly researched the relevant papers and included appropriate citations! Especially, make sure that you have found, read, and included all the latest publications on your topic before finalizing and submitting your own paper—if the drafting process took some time, new literature might have come out in the meantime, and you don’t want to give the editor the impression that you are not on top of the newest developments.
  • If you have too many references, readers may wonder if you did any original research at all. Unless you’re writing a literature review, your paper’s primary focus should be on your investigation and findings. Don’t bury your hard work under strings of citations and discussion regarding other works. Show your readers what you’ve discovered and how the new information you present fits into or departs from the academic community’s current understanding of your topic.

Additionally, let us highlight the difference between the number of references versus citations. References are the source materials; therefore, each reference should be listed only once in your references section. Citations are meant to identify the source of the information you use in your paper. You can cite a reference multiple times. Therefore, the number of citations you have is typically larger than the number of references an average paper includes. The opposite situation should never happen!

Key Factors Influencing the Number of References You Use

The following are some of the many factors that may influence the number of references you use:

  • The number of references required for a paper will depend largely on your work’s purpose . For example, literature and systematic reviews are surveys of existing studies. Therefore, their reference lists will be more exhaustive than those of research papers whose primary focus is the current authors’ findings. Indeed, if you examine many journals’ author guidelines , you’ll note that journals have a higher maximum reference limit for review articles than original research papers.
  • The length of your reference list will also depend on your research paper’s subject matter . For example, if you are writing about a field that is less studied (such as a subfield of neuroparasitology) you may discover that there aren’t many papers to cite. Similarly, newer fields will have fewer published papers that can be referenced. If you find yourself in this situation, review the references used by relevant current literature and see if you can expand your research, and thus your reference list, with valuable content from there.
  • Another factor will be your  institution or journal’s requirements . If you are preparing a dissertation or thesis, double-check your department’s requirements. While rare, they may have specific limits. More commonly, journals restrict the number of references due to printing constraints.
  • It may happen that you don’t have  access to certain literature  that could have served as a reference. In such a situation, you may wish to look for an institution that may be able to provide you access to that literature for the purposes of reviewing the content or contact one of the authors directly and ask for a copy.
  • Given that more papers are being published than ever before in most fields, it is likely that reference lists will grow longer simply because there are more data and discussions of existing data available to cite . Keep track of changes to the size of reference lists in publications related to your field.
  • Finally, a paper’s length bears some correlation to the number of references.

So how many references should be included?

Below, we provide tips on how to decide if you have enough resources. We also provide some general reminders on how to effectively use references. After all, references are meant to enhance your paper while still maintaining your research as the focal point.

Use academic journals as a guide

  • One way to gauge how many references you should have is to survey academic journals for your article type in your field. Review their author guidelines for limits on the number of references for your article type, and make sure your reference list complies with those journal restrictions.
  • Read recent articles relevant to your topic; check how many references other authors have included in their papers for the same article type as yours, and how frequently those works were cited per page.
  • Keep in mind that the above methods will give you an estimate of how many references you should include overall but will not tell you how many citations you’ll need per page. The latter is impossible to state simply because certain sections may have no citations at all (the results section , for example).

Statistics regarding the number of references and citations

To give you a general idea, the following are some estimates from a couple of studies that examined the citation characteristics of articles published in various disciplines.

According to  Milojević’s study  encompassing research in the fields of astronomy, mathematics, robotics, ecology, and economics, the highest and average number of references per article page were as follows:

  • Ecology: highest, ~58; average reference per page, 6;
  • Math and robotics: highest, ~28; average reference per page, <1; and
  • Economics: highest, ~ 32; average reference per page, >1 but <2.

The above findings were based on data compiled from the first 20 years of the author’s research. Since then some fields have increased the number of references. Thus, make sure to examine your target journal’s most recent and relevant publications for a better idea of how many references to include based on the specific type of article you plan to write.

In another study by Falagas et al. (2013),  medical journals averaged  29 references for articles that were 7.88 pages long (as printed in journals).

Finally, although the sample size was small (63 journals), Gali Halevi observed the following citation trends of a broader range of disciplines.

  • The average number of references per article was the highest for the social sciences, physics, and astronomy, and arts & humanities (roughly 54 references per article).
  • On the other hand, health professions and earth and planetary sciences had the fewest references per article at an average of 8 and 17 references, respectively.
  • Math and engineering averaged at roughly 29 references per article.
  • Biochemistry, genetics and molecular and other biological sciences averaged at 51.
  • Hard and natural sciences more frequently cited recent literature while social sciences and math were likely to include older sources.

Note that the Halevi study is limited in size, fails to factor in article type and does little to account for variances across different fields and journals. For example, it is possible that more review articles could have been reviewed for certain fields than others. With that said, we provide the above information to provide a rough estimate.

At the end of the day, please keep in mind the requirements of your institution or target journal and the general trends for your specific article type (by examining the most recent relevant publications).

For additional information regarding journal restrictions on the number of references, read this article on ways to grow your publication list .

Some Dos and Don’ts for Reference Citation

  • Don’t repeat references within a reference list.
  • Don’t repeatedly cite yourself. Make sure to balance your discussion with external literature citations.
  • Be careful about citing old references. The rule of thumb is to go back at most five to six years. Exceptions to this rule should be reserved for “seminal” works relevant to explaining what prompted your research. Roughly 85% of all cited works should be less than five years old.
  • Be careful not to cite several references in one place  without  discussing the relevance of each work to your research. In other words, don’t say, “We referred to previous studies in this field (1-7)” unless you later explain how each of reference #s 1-7 apply to your discussion.
  • Confirm the quality of the work you cite. Are there any ethical issues regarding the paper that would disqualify it as a good source? Do your references come from reputable sources such as respected journals rather than random blogs and website links? Remember that your analysis is only as good as the verifiable information you use to conduct your research.
  • One of the main purposes of citing existing literature is to show the “knowledge gap” regarding your topic. Therefore, make sure the works you reference naturally lead readers to wonder about the research question you address in your paper. To explain further, think about your favorite fictional story. A successfully written story only reveals the background information needed for the reader to follow along in the story. You’ll rarely see an author waste time writing about how the main character stubbed his toe one day while going to work unless that event relates to an important aspect of the story. Similarly, the references you cite should support the story building you create in your research paper.
  • Don’t completely ignore the paper that could disprove your hypothesis. You want to show objectivity and that you took a balanced and unbiased approach to conducting your research. Mention the potentially conflicting evidence and explain why you believe it is flawed or inapplicable to your research.
  • In qualitative research papers, you may have fewer references.
  • Anything you cite in your paper should be listed in the references section (or reference list). Anything listed as a reference should have been quoted or paraphrased in the text. If either rule is violated, something is wrong.
  • Finally, remember that a paper will typically have more citations in the Introduction section and Discussion section than in other parts.

Wordvice Academic Resources

If you need help with paraphrasing text from the sources you cite to avoid plagiarism, with different citation styles , or with finding the perfect journal to submit your paper to, then have a look at our collection of articles on the Wordvice academic resources website . We also recommend our professional English editing and proofreading services , including paper editing and academic editing services to ensure that your writing is free of errors before submitting your manuscript to a journal.

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How many references should I have?

Use as many references as you need You’ll need an appropriate amount for your academic level – this will vary

Reference everything you cite  If you use an idea, cite and reference it

Ask your tutor They may have guidance for you on how much reading they expect you to do

Students sometimes worry that there is an optimum number of references that they need to cite.

There’s no right or wrong answer  answer as to how many references you need – it depends on how many you’ve cited in your writing!

The most important thing is that you don’t plagiarise. Make sure you include references for everything that you’ve cited in the text, so that it’s clear where your information has come from.

Depending on what you’re writing, you might have only a few. As long as they are appropriate for your level of study, and you have enough evidence to back your arguments, you shouldn’t worry.  Lab reports, for example, might have relatively few references because you are writing up work that you have done in the labs.  

You can also look at the marking criteria for your assignment as that might indicate on what is or isn’t sufficient. If in doubt, check with whoever set you the work as they might be able to give you a clearer idea.

Remember, you are looking to provide proof that you have done the research. Citations and referencing point your readers to the sources you have used in your research process.  

Citation guides

All you need to know about citations

How to cite a PhD thesis in Harvard

Harvard PhD thesis citation

To cite a PhD thesis in a reference entry in Harvard style include the following elements:

  • Author(s) of the PhD thesis: Give the last name and initials (e. g. Watson, J.) of up to three authors with the last name preceded by 'and'. For four authors or more include the first name followed by et al., unless your institution requires referencing of all named authors.
  • Year of submission: Give the year in round brackets.
  • Title of the PhD thesis: Give the title as presented in the source. Only the first letter of the first word and proper nouns are capitalized.
  • Degree description: Type of degree.
  • Degree-awarding institution: Give the name of the institution.

Here is the basic format for a reference list entry of a PhD thesis in Harvard style:

Author(s) of the PhD thesis . ( Year of submission ) Title of the PhD thesis . Degree description . Degree-awarding institution .

Take a look at our reference list examples that demonstrate the Harvard style guidelines in action:

A PhD thesis with one author

Confait, M. F . ( 2018 ) Maximising the contributions of PHD graduates to national development: the case of the Seychelles . PhD thesis . Edith Cowan University .

An unpublished PhD thesis

Bowkett, D . ( 2015 ) Investigating the ligandability of plant homeodomains . Unpublished PhD thesis . University of Oxford .

harvard cover page

This citation style guide is based on the Cite Them Right (10 th edition) Harvard referencing guide.

More useful guides

  • Harvard Referencing: Theses
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In-Text References, Footnotes, Endnotes, Tables & Figures in PhD Theses

Posted by Rene Tetzner | Oct 5, 2021 | PhD Success | 0 |

In-Text References, Footnotes, Endnotes, Tables & Figures in PhD Theses

1.2.6 In-Text References, Footnotes and/or Endnotes

References to the sources cited and/or quoted in a thesis should appear throughout the thesis. Depending on the discipline, university and department guidelines and the requirements of the individual thesis, in-text citations may take the form of numerical references, be based on the last names of authors (usually along with publication dates) or appear in footnotes or endnotes. Footnotes and endnotes can also be used to provide a wide variety of material beyond bibliographical references, such as summaries of the scholarship on a topic, suggestions for further reading, alternative or contradictory editions and arguments, and further details on anything discussed in the main text.

Both kinds of notes are usually indicated by superscript Arabic numerals, with the numbering often beginning again at the start of each chapter, and the notes themselves are generally set in a slightly smaller font than that of the main text of a thesis. Footnotes appear at the bottom of the relevant pages, but endnotes can appear either at the end of each chapter or in the final matter of the thesis. For more information on footnotes, endnotes and in-text references, see Sections 1.4 and 3.4 as well as Chapter 7.

how many references should a phd thesis have

1.3 Tables and Figures

The tables and figures included in a thesis will often appear in the main body of the thesis with each one placed as close as possible to the discussion of it in the text, or to the report or description it enhances or illustrates. This is not always the case, however: some universities, departments, thesis committees and doctoral candidates will want tables and figures placed at the end of the thesis (or the tables and figures for each chapter placed at the end of that chapter), which simplifies the layout of the text itself and is particularly appropriate for especially long tables or large figures.

In some cases, certain tables and figures might be embedded in the main body of the thesis while others will be tacked on at the end. As a general rule, each table or figure should be able to stand on its own, which is to say that all the information necessary to understand the table or figure without recourse to other parts of the thesis should be provided in the context of the table or figure. For guidance on designing, incorporating and listing tables and figures, see Sections 1.1.8 and 1.1.9 and Sections 4.4.1 and 4.6.

how many references should a phd thesis have

1.3.1 Tables

Tables consist of columns and rows and are used to present data in a visually effective way that more readily allows for comprehension, calculation and/or comparison than describing the same data in text could. Tables should be numbered, usually with Arabic numerals (Roman numerals or letters are much rarer), in the order in which they are first mentioned in the thesis (see Section 4.6.1 for advice on numbering tables that appear in appendices), and each table should bear a title or main heading that indicates exactly what the table shows.

Each table must be referred to in the text by its number along with some indication of what the reader will find in the table, and the tables themselves should appear in their order of mention whether they are embedded in the text or placed at the end of a chapter or the end of the thesis as a whole. Headings on columns and rows within a table define the data presented and, if necessary, notes at the bottom explain aspects that might otherwise be unclear to readers, such as abbreviations and probability values. There may be specific university or department guidelines for the use and layout of tables, but, generally speaking, clarity, accuracy and consistency are the keys to well-designed tables.

how many references should a phd thesis have

1.3.2 Figures

Figures take many forms including charts, graphs, plots, boxes, photographs, drawings and maps that illustrate or clarify aspects of the research and results presented in a thesis. Like tables, figures should be numbered with Arabic numerals (more rarely Roman numerals or letters) in the order in which they are first mentioned in the thesis (see Section 4.6.1 for advice on numbering figures that appear in appendices), and each figure should bear a caption describing exactly what the figure shows. Each figure should also be referred to in the text by its number along with some indication of what the reader will find in the figure, and the figures themselves should appear in their order of mention, whether they are embedded in the text or placed at the end of a chapter or the end of the thesis as a whole.

Labelling within a figure identifies aspects of the illustration, a key can be used to provide scales and define tints, and explanatory notes for abbreviations and the like can be included in either the caption or a legend. University or department requirements should always be consulted for specific guidance on the use and format of figures, but as a general rule, an attractive appearance clearly incorporating all the information needed to enable the reader’s comprehension of its significance is central to the design of a successful figure.

1.4 Final and Supplementary Matter

1.4.1 Appendices

Appendices (occasionally called appendixes or annexes) are not required in a thesis, but they may certainly be used if necessary. Material that supports or is closely related to the information provided in the main body of a thesis but too long or detailed to be included there or in notes, or material relevant to more than one chapter or section of a thesis is usually placed in an appendix unless university or department requirements do not allow appendices. Appendices sometimes appear in a slightly smaller font than the main text of a thesis and are often labelled with uppercase letters (‘A,’ ‘B,’ ‘C,’ etc.) rather than numbers, but Arabic or Roman numerals are also acceptable. 

how many references should a phd thesis have

Each appendix should be referred to by its letter or number in the thesis along with some indication of what the reader will find in the appendix, and the appendices themselves should be arranged according to the order of mention. Appendices always appear in the final matter and generally precede any endnotes as well as the reference list, but in some fields the appendices will be the last items in a thesis. For more information on appendices, see Sections 3.5.3 and 4.6.1.

1.4.2 Endnotes

If endnotes are used instead of footnotes for references in the main text of a thesis, for supplementary material or for a combination of both, they appear at the end of the thesis before the list of references or at the end of each chapter. If they are placed at the end of each chapter, the layout clearly indicates to which chapter the notes apply, but if they appear at the end of the thesis, headings within the endnotes should indicate to which chapter each group of notes apply. Endnotes often use a font slightly smaller than that of the main text of the thesis and are usually indicated by superscript Arabic numerals, but if both footnotes and endnotes are necessary (the first for supplementary material, for instance, and the second for textual notes), different indicators should be used for the two kinds of notes (superscript Arabic numerals for footnotes, for example, and bracketed Arabic numerals for endnotes). For more information on endnotes, see Section 1.2.6 above and Sections 3.4 and 7.2.3 below.

1.4.3 List of References, List of Works Cited or Bibliography

Every thesis requires a list of the sources used while writing the thesis, usually even if full bibliographical references are provided in footnotes or endnotes. A list of references or works cited normally contains only those sources actually cited in the thesis, whereas a bibliography can also contain any additional sources consulted. The list is usually arranged either alphabetically (by the last names of authors) or numerically, depending on the referencing system used, although it can also be subdivided into sections with headings such as ‘Primary Sources,’ ‘Secondary Literature’ and ‘Randomised Controlled Trials.’ Disciplines and departments tend to prefer specific referencing systems and styles, so do check any relevant guidelines and follow them carefully. Accuracy and thoroughness are paramount in reference lists, and, as much as possible, the style and content of the references should remain consistent throughout the list. For more information on lists of references, see Section 3.5.4 and Chapter 7 below.

PRS Tip: If you find that you are having difficulties designing an appropriate structure for your thesis, your supervisor and perhaps other members of your thesis committee should be able to help you determine the topics, chapters, sections and, more generally, material that are required for your discipline and department. Your department may have guidelines or templates outlining the structure of doctoral theses that will prove helpful, so do check into this, and if not, looking at successful theses that have recently been completed in your department to determine how they are organised can provide sound examples. You may also find it helpful, however, to send an early draft of your thesis or proposal chapters to PRS for proofreading. PRS not only uses professional proofreaders who specialise in a wide range of academic and scientific areas, but can also provide proofreaders who work primarily on doctoral theses. Such proofreaders are well versed in what theses in different disciplines should contain and how they should be arranged, and they are also able to read your work within the broad context of the many doctoral theses they encounter each month. Their advice should not, of course, take precedence over that of your supervisor and committee members, who are experts in your area of study and usually also examiners of your thesis, but the objective perspective of a professional proofreader who is familiar with academic and scientific writing and alert to details of all kinds can be immensely helpful. You can also send along with your work any instructions you may have been given regarding the structure and organisation of your thesis so that your proofreader can help you tailor your thesis with precision.

Why PhD Success?

To Graduate Successfully

This article is part of a book called "PhD Success" which focuses on the writing process of a phd thesis, with its aim being to provide sound practices and principles for reporting and formatting in text the methods, results and discussion of even the most innovative and unique research in ways that are clear, correct, professional and persuasive.

how many references should a phd thesis have

The assumption of the book is that the doctoral candidate reading it is both eager to write and more than capable of doing so, but nonetheless requires information and guidance on exactly what he or she should be writing and how best to approach the task. The basic components of a doctoral thesis are outlined and described, as are the elements of complete and accurate scholarly references, and detailed descriptions of writing practices are clarified through the use of numerous examples.

how many references should a phd thesis have

The basic components of a doctoral thesis are outlined and described, as are the elements of complete and accurate scholarly references, and detailed descriptions of writing practices are clarified through the use of numerous examples. PhD Success provides guidance for students familiar with English and the procedures of English universities, but it also acknowledges that many theses in the English language are now written by candidates whose first language is not English, so it carefully explains the scholarly styles, conventions and standards expected of a successful doctoral thesis in the English language.

how many references should a phd thesis have

Individual chapters of this book address reflective and critical writing early in the thesis process; working successfully with thesis supervisors and benefiting from commentary and criticism; drafting and revising effective thesis chapters and developing an academic or scientific argument; writing and formatting a thesis in clear and correct scholarly English; citing, quoting and documenting sources thoroughly and accurately; and preparing for and excelling in thesis meetings and examinations. 

how many references should a phd thesis have

Completing a doctoral thesis successfully requires long and penetrating thought, intellectual rigour and creativity, original research and sound methods (whether established or innovative), precision in recording detail and a wide-ranging thoroughness, as much perseverance and mental toughness as insight and brilliance, and, no matter how many helpful writing guides are consulted, a great deal of hard work over a significant period of time. Writing a thesis can be an enjoyable as well as a challenging experience, however, and even if it is not always so, the personal and professional rewards of achieving such an enormous goal are considerable, as all doctoral candidates no doubt realise, and will last a great deal longer than any problems that may be encountered during the process.

how many references should a phd thesis have

Interested in Proofreading your PhD Thesis? Get in Touch with us

If you are interested in proofreading your PhD thesis or dissertation, please explore our expert dissertation proofreading services.

how many references should a phd thesis have

Rene Tetzner

Rene Tetzner's blog posts dedicated to academic writing. Although the focus is on How To Write a Doctoral Thesis, many other important aspects of research-based writing, editing and publishing are addressed in helpful detail.

Related Posts

PhD Success – How To Write a Doctoral Thesis

PhD Success – How To Write a Doctoral Thesis

October 1, 2021

Table of Contents – PhD Success

Table of Contents – PhD Success

October 2, 2021

The Essential – Preliminary Matter

The Essential – Preliminary Matter

October 3, 2021

The Main Body of the Thesis

The Main Body of the Thesis

October 4, 2021

How Many References Should a Research Paper Have? Study of 96,685 Articles

I analyzed a random sample of 96,685 full-text research papers, uploaded to PubMed Central between the years 2016 and 2021, in order to answer the question:

How many references should you cite when writing a research article?

I used the BioC API to download the data (see the References section below).

Here’s a summary of the key findings

1- The average number of references for a research paper is 45 , with 90% of research papers having between 8 and 102 references. However, this number depends a lot on study design . For instance, a systematic review typically has 49 references while a case report has only 24.

2- As a rule of thumb, consider citing 1 reference for every 95 words (or 4 sentences) .

3- The more research you do will be reflected in the number of references you use in your paper, since high-quality articles usually have 5 more references than the median .

How many references does a typical article have?

The histogram below shows that most research papers have between 25 to 50 references, and only a few exceed 100:

Histogram showing that most articles have between 0 and 100 references and only a few have more than 100 references.

Because the distribution has a right tail, the median number of references becomes a more reliable metric than the mean. Here are a few other numbers that summarize the data:

From this table we can conclude that:

The median research paper has 39 references, and 50% of papers have between 25 and 56 references. An article can have as few as 1 reference as a minimum, and 911 references as a maximum.

Next, let’s see if the number of references depends on the study design.

Should the study design influence the number of references you use?

The table below shows that:

1- Secondary study designs (systematic reviews and meta-analyses) have the highest number of references (median = 49), which is to be expected as these articles review a large body of information.

2- Experimental, quasi-experimental and analytical designs typically have between 35 and 39 references.

3- Descriptive designs (case reports and case series) have the lowest number of references (median ≈ 25), which also makes sense as these describe the clinical story of a single (or a few) patient(s) and generally have a very short literature review section.

How often should you cite in a research paper?

Some journals may specify the maximum number of citations allowed. For instance, Nature allows articles to have at most 30 references in the main text [ Source ]. So make sure to check the authorship guidelines of the journal where you want to submit.

That being said, often is the case where we ask ourselves: am I taking too much information from outside sources? or maybe too few? So I would argue that it would be useful to know, for a given article size, how many references to cite.

If we measure the length of all the articles in our dataset combined and divide it by the total number of references, we get the following numbers:

On average, 1 reference is cited for every 95 words, that is 1 reference for every 4 sentences. In terms of paragraphs, an article has approximately 1.5 references for each paragraph.

Here’s a table that shows the median number of references cited for each word count category:

Does using more references make your article better?

Hypothesis 1: It is well-known that citing more resources is usually associated with more in-depth research, therefore, we would expect high-quality articles to include a higher number of references.

Hypothesis 2: Some experts believe that a good writing habit is to keep the number of references to a minimum (see: Essentials of Writing Biomedical Research Papers by Mimi Zeiger), so according to this hypothesis, high-quality articles should have, on average, fewer references.

Let’s find out what researchers are doing in practice and which hypothesis our data support.

In order to answer the question, I collected the journal impact factor (JIF) for 71,579 articles and divided the dataset into 2 groups:

  • research papers published in low impact journals (JIF ≤ 3): this subset consisted of 34,758 articles
  • research papers published in high impact journals (JIF > 3): this subset consisted of 36,821 articles

After controlling for study design, the group with JIF ≤ 3 had a median number of references of 37, while the group with JIF > 3 had a median of 44.

Remember that the median article overall had 39 references (as we saw above), so based on these results, we can conclude that:

High-quality articles, in general, have about 5 more references than the median article. So a comprehensive literature review and a more in-depth discussion section can make the difference between a good and an excellent research article.

  • Comeau DC, Wei CH, Islamaj Doğan R, and Lu Z. PMC text mining subset in BioC: about 3 million full text articles and growing,  Bioinformatics , btz070, 2019.

Further reading

  • How Old Should References Be? Based on 3,823,919 Examples
  • Statistical Software Popularity in 40,582 Research Papers
  • Programming Languages Popularity in 12,086 Research Papers
  • Length of a Conclusion Section: Analysis of 47,810 Examples
  • How Long Should a Research Paper Be? Data from 61,519 Examples

The Graduate College at the University of Illinois at Urbana-Champaign

Bibliography or references.

Refer to the Sample Bibliography or References pages as you read through this section.

There is no reference style required by the Graduate College Thesis Office. However, departments may require the use of a reference style that is appropriate to the student’s program of study.

  • All theses are required to have either a bibliography or a list of references.
  • When placed at or near the end of a thesis, the references section is considered a chapter equivalent; therefore, the title of the section should be formatted like a chapter title.
  • In some scientific and engineering disciplines, the references may be placed at the end of each chapter instead of at the end of the thesis.

Citation of previously published material

Inclusion of work that has been previously published by the degree candidate is a common practice in research institutions across the country, and it is permitted at the University of Illinois. In such cases, the Graduate College requires that the student state at the beginning of the chapter that the work includes previously published material.

This is accomplished by including a footnote at the bottom of the first page of the chapter in which the previously published material appears that acknowledges the previous publication, cites basic bibliographic information, and states that the copyright owner has provided permission to reprint. In scientific disciplines, it is also common for students to include material derived from a published paper with multiple authors. In such cases, the footnote must acknowledge the contribution of the other authors, including any figures, tables, or data that were not created by the author.

Students with further questions regarding copyright and the use of previously published material should refer to copyright information and resources .

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To be made up of:

  • Year of submission (in round brackets).
  • Title of thesis (in italics).
  • Degree statement.
  • Degree-awarding body.
  • Available at: URL.
  • (Accessed: date).

In-text citation: 

(Smith, 2019)

Reference List:  

Smith, E. R. C. (2019). Conduits of invasive species into the UK: the angling route? Ph. D. Thesis. University College London. Available at: https://discovery.ucl.ac.uk/id/eprint/10072700 (Accessed: 20 May 2021).

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Literature reviews

Writing a literature review.

The following guide has been created for you by the  Student Learning Advisory Service . For more detailed guidance and to speak to one of our advisers, please book an  appointment  or join one of our  workshops . Alternatively, have a look at our  SkillBuilder  skills videos.   

Preparing a literature review involves:

  • Searching for reliable, accurate and up-to-date material on a topic or subject
  • Reading and summarising the key points from this literature
  • Synthesising these key ideas, theories and concepts into a summary of what is known
  • Discussing and evaluating these ideas, theories and concepts
  • Identifying particular areas of debate or controversy
  • Preparing the ground for the application of these ideas to new research

Finding and choosing material

Ensure you are clear on what you are looking for. ask yourself:.

  • What is the specific question, topic or focus of my assignment?
  • What kind of material do I need (e.g. theory, policy, empirical data)?
  • What type of literature is available (e.g. journals, books, government documents)?

What kind of literature is particularly authoritative in this academic discipline (e.g. psychology, sociology, pharmacy)?

How much do you need?

This will depend on the length of the dissertation, the nature of the subject, and the level of study (undergraduate, Masters, PhD). As a very rough rule of thumb – you may choose 8-10 significant pieces (books and/or articles) for an 8,000 word dissertation, up to 20 major pieces of work for 12-15,000 words, and so on. Bear in mind that if your dissertation is based mainly around an interaction with existing scholarship you will need a longer literature review than if it is there as a prelude to new empirical research. Use your judgement or ask your supervisor for guidance.

Where to find suitable material

Your literature review should include a balance between substantial academic books, journal articles and other scholarly publications. All these sources should be as up-to-date as possible, with the exception of ‘classic texts’ such as major works written by leading scholars setting out formative ideas and theories central to your subject. There are several ways to locate suitable material:

Module bibliography: for undergraduate dissertations, look first at the bibliography provided with the module documentation. Choose one or two likely looking books or articles and then scan through the bibliographies provided by these authors. Skim read some of this material looking for clues: can you use these leads to identify key theories and authors or track down other appropriate material?

Library catalogue search engine: enter a few key words to capture a range of items, but avoid over-generalisations; if you type in something as broad as ‘social theory’ you are likely to get several thousand results. Be more specific: for example, ‘Heidegger, existentialism’. Ideally, you should narrow the field to obtain just a few dozen results. Skim through these quickly to identity texts which are most likely to contribute to your study.

Library bookshelves: browse the library shelves in the relevant subject area and examine the books that catch your eye. Check the contents and index pages, or skim through the introductions (or abstracts, in the case of journal articles) to see if they contain relevant material, and replace them if not. Don’t be afraid to ask one of the subject librarians for further help. Your supervisor may also be able to point you in the direction of some of the important literature , but remember this is your literature search, not theirs.

Online: for recent journal articles you will almost certainly need to use one of the online search engines. These can be found on the ‘Indexing Services’ button on the Templeman Library website. Kent students based at Medway still need to use the Templeman pages to access online journals, although you can get to these pages through the Drill Hall Library catalogue. Take a look as well at the Subject Guides on both the Templeman and DHL websites.

Check that you have made the right selection by asking:

  • Has my search been wide enough to ensure that I have identified all the relevant material, but narrow enough to exclude irrelevant material?
  • Is there a good enough sample of literature for the level (PhD, Masters, undergraduate) of my dissertation or thesis?
  • Have I considered as many alternative points of view as possible?
  • Will the reader find my literature review relevant and useful?

Assessing the literature

Read the material you have chosen carefully, considering the following:

  • The key point discussed by the author: is this clearly defined
  • What evidence has the author produced to support this central idea?
  • How convincing are the reasons given for the author’s point of view?
  • Could the evidence be interpreted in other ways?
  • What is the author's research method (e.g. qualitative, quantitative, experimental, etc.)?
  • What is the author's theoretical framework (e.g. psychological, developmental, feminist)?
  • What is the relationship assumed by the author between theory and practice?
  • Has the author critically evaluated the other literature in the field?
  • Does the author include literature opposing their point of view?
  • Is the research data based on a reliable method and accurate information?
  • Can you ‘deconstruct’ the argument – identify the gaps or jumps in the logic?
  • What are the strengths and limitations of this study?
  • What does this book or article contribute to the field or topic?
  • What does this book or article contribute to my own topic or thesis?

As you note down the key content of each book or journal article (together with the reference details of each source) record your responses to these questions. You will then be able to summarise each piece of material from two perspectives:     

Content: a brief description of the content of the book or article. Remember, an author will often make just one key point; so, what is the point they are making, and how does it relate to your own research project or assignment?

Critical analysis: an assessment of the relative strengths and weaknesses of the evidence used, and the arguments presented. Has anything conveniently been left out or skated over? Is there a counter-argument, and has the author dealt with this adequately? Can the evidence presented be interpreted another way? Does the author demonstrate any obvious bias which could affect their reliability? Overall, based on the above analysis of the author’s work, how do you evaluate its contribution to the scholarly understanding and knowledge surrounding the topic?    

Structuring the literature review

In a PhD thesis, the literature review typically comprises one chapter (perhaps 8-10,000 words), for a Masters dissertation it may be around 2-3,000 words, and for an undergraduate dissertation it may be no more than 2,000 words. In each case the word count can vary depending on a range of factors and it is always best, if in doubt, to ask your supervisor.

The overall structure of the section or chapter should be like any other: it should have a beginning, middle and end. You will need to guide the reader through the literature review, outlining the strategy you have adopted for selecting the books or articles, presenting the topic theme for the review, then using most of the word limit to analyse the chosen books or articles thoroughly before pulling everything together briefly in the conclusion.

Some people prefer a less linear approach. Instead of simply working through a list of 8-20 items on your book review list, you might want to try a thematic approach, grouping key ideas, facts, concepts or approaches together and then bouncing the ideas off each other. This is a slightly more creative (and interesting) way of producing the review, but a little more risky as it is harder to establish coherence and logical sequencing.

Whichever approach you adopt, make sure everything flows smoothly – that one idea or book leads neatly to the next. Take your reader effortlessly through a sequence of thought that is clear, accurate, precise and interesting. 

Writing up your literature review

As with essays generally, only attempt to write up the literature review when you have completed all the reading and note-taking, and carefully planned its content and structure. Find an appropriate way of introducing the review, then guide the reader through the material clearly and directly, bearing in mind the following:

  • Be selective in the number of points you draw out from each piece of literature; remember that one of your objectives is to demonstrate that you can use your judgement to identify what is central and what is secondary.
  • Summarise and synthesise – use your own words to sum up what you think is important or controversial about the book or article.
  • Never claim more than the evidence will support. Too many dissertations and theses are let down by sweeping generalisations. Be tentative and careful in the way you interpret the evidence.
  • Keep your own voice – you are entitled to your own point of view provided it is based on evidence and clear argument.
  • At the same time, aim to project an objective and tentative tone by using the 3rd person, (for example, ‘this tends to suggest’, ‘it could be argued’ and so on).
  • Even with a literature review you should avoid using too many, or overlong, quotes. Summarise material in your own words as much as possible. Save the quotes for ‘punch-lines’ to drive a particular point home.
  • Revise, revise, revise: refine and edit the draft as much as you can. Check for fluency, structure, evidence, criticality and referencing, and don’t forget the basics of good grammar, punctuation and spelling.

how many references should a phd thesis have

  • How Long Is a PhD Thesis?
  • Doing a PhD

It’s no secret that one of the most challenging aspects of a PhD degree is the volume of work that goes into writing your thesis . So this raises the question, exactly how long is a thesis?

Unfortunately, there’s no one size fits all answer to this question. However, from the analysis of over 100 PhD theses, the average thesis length is between 80,000 and 100,000 words. A further analysis of 1000 PhD thesis shows the average number of pages to be 204 . In reality, the actual word count for each PhD thesis will depend on the specific subject and the university it is being hosted by. This is because universities set their own word length requirements, with most found to be opting for around 100,000.

To find out more about how these word limits differ between universities, how the average word count from STEM thesis differ from non-STEM thesis and a more detailed breakdown from the analysis of over 1000 PhDs, carry on reading the below.

Word Count Differences Between Universities

For any PhD student writing a thesis, they will find that their document will be subject to a word limit set by their university. In nearly all cases, the limit only concerns the maximum number of words and doesn’t place any restrictions on the minimum word limit. The reason for this is that the student will be expected to write their thesis with the aim of clearly explaining their research, and so it is up to the student to determine what he deems appropriate.

Saying this, it is well accepted amongst PhD students and supervisors that the absence of a lower limit doesn’t suggest that a thesis can be ‘light’. Your thesis will focus on several years worth of original research and explore new ideas, theories or concepts. Besides this, your thesis will need to cover a wide range of topics such as your literature review, research methodology, results and conclusion. Therefore, your examiners will expect the length of your thesis to be proportional to convey all this information to a sufficient level.

Selecting a handful of universities at random, they state the following thesis word limits on their website:

  • University of Edinburgh: 100,000
  • University of Exeter: 100,000
  • University of Leister: 80,000
  • University of Bath: 80,000
  • University of Warwick: 70,000

The above universities set upper word limits that apply across the board, however, some universities, such as the University of Birmingham and the University of Sheffield, set different word limits for different departments. For example, the University of Sheffield adopts these limits:

  • Arts & Humanities: 75,000
  • Medicine, Dentistry & Health: 75,000
  • Science: 80,000
  • Social Sciences: 75,000-100,000

Although there’s a range of limit, it’s safe to say that the majority fall within the 80,000 to 100,000 bracket.

Word Count Based on Data from past Theses

A poll of 149 postdocs.

In mid-2019, Dr Eva Lantsoght, a published author, academic blogger and Structural Engineering Professor, conducted a poll which asked postgraduate doctoral students to share the length of their final thesis. 149 PostDoc students responded to the survey, with the majority reporting a length falling within the ‘80,000 – 120,000 words’ bracket as seen below.

DiscoverPhDs_How-long-is-a-PhD-Thesis_Poll

Analysis of 1000 PhD Theses

Over a three-year time period, Dr Ian Brailsford, a then Postgraduate Learning Adviser at the University of Auckland, analysed 1000 doctoral thesis submitted to his university’s library. The PhD theses which formed the basis of his analysis were produced between 2008 to 2017 and showed:

  • Average number of pages = 204
  • Median number of pages = 198
  • Average number of chapters = 7.6

We should note that the above metrics only cover the content falling within the main body of the thesis. This includes the introduction, literature review, methods section, results chapter, discussions and conclusions. All other sections, such as the title page, abstract, table of contents, acknowledgements, bibliography and appendices were omitted from the count.

Although it’s impossible to draw the exact word count from the number of pages alone, by using the universities recommended format of 12pt Times New Roman and 1.5 lines spacing, and assuming 10% of the main body are figures and footnotes, this equates to an average main body of 52,000 words.

STEM vs Non-STEM

As part of Dr Ian Brailsford’s analysis, he also compared the length of STEM doctorate theses to non-STEM theses. He found that STEM theses tended to be shorter. In fact, he found STEM theses to have a medium page length of 159 whilst non-STEM theses had a medium of around 223 pages. This is a 40% increase in average length!

Can You Exceed the Word Count?

Whilst most universities will allow you to go over the word count if you need to, it comes with the caveat that you must have a very strong reason for needing to do so. Besides this, your supervisor will also need to support your request. This is to acknowledge that they have reviewed your situation and agree that exceeding the word limit will be absolutely necessary to avoid detriment unnecessary detriment to your work.

This means that whilst it is possible to submit a thesis over 100,000 words or more, it’s unlikely that your research project will need to.

How Does This Compare to a Masters Dissertation?

The average Masters dissertation length is approximately 20,000 words whilst a thesis is 4 to 5 times this length at approximately 80,000 – 100,000.

The key reason for this difference is because of the level of knowledge they convey. A Master’s dissertation focuses on concluding from existing knowledge whilst a PhD thesis focuses on drawing a conclusion from new knowledge. As a result, the thesis is significantly longer as the new knowledge needs to be well documented so it can be verified, disseminated and used to shape future research.

Finding a PhD has never been this easy – search for a PhD by keyword, location or academic area of interest.

Related Reading

Unfortunately, the completion of your thesis doesn’t mark the end of your degree just yet. Once you submit your thesis, it’s time to start preparing for your viva – the all-to-fun thesis defence interview! To help you prepare for this, we’ve produced a helpful guide which you can read here: The Complete Guide to PhD Vivas.

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On this page:

Language of the Dissertation

Page and text requirements, body of text, tables, figures, and captions, dissertation acceptance certificate, copyright statement.

  • Table of Contents

Front and Back Matter

Supplemental material, dissertations comprising previously published works, top ten formatting errors, further questions.

  • Related Contacts and Forms

When preparing the dissertation for submission, students must follow strict formatting requirements. Any deviation from these requirements may lead to rejection of the dissertation and delay in the conferral of the degree.

The language of the dissertation is ordinarily English, although some departments whose subject matter involves foreign languages may accept a dissertation written in a language other than English.

Most dissertations are 100 to 300 pages in length. All dissertations should be divided into appropriate sections, and long dissertations may need chapters, main divisions, and subdivisions.

  • 8½ x 11 inches, unless a musical score is included
  • At least 1 inch for all margins
  • Body of text: double spacing
  • Block quotations, footnotes, and bibliographies: single spacing within each entry but double spacing between each entry
  • Table of contents, list of tables, list of figures or illustrations, and lengthy tables: single spacing may be used

Fonts and Point Size

Use 10-12 point size. Fonts must be embedded in the PDF file to ensure all characters display correctly. 

Recommended Fonts

If you are unsure whether your chosen font will display correctly, use one of the following fonts: 

If fonts are not embedded, non-English characters may not appear as intended. Fonts embedded improperly will be published to DASH as-is. It is the student’s responsibility to make sure that fonts are embedded properly prior to submission. 

Instructions for Embedding Fonts

To embed your fonts in recent versions of Word, follow these instructions from Microsoft:

  • Click the File tab and then click Options .
  • In the left column, select the Save tab.
  • Clear the Do not embed common system fonts check box.

For reference, below are some instructions from ProQuest UMI for embedding fonts in older file formats:

To embed your fonts in Microsoft Word 2010:

  • In the File pull-down menu click on Options .
  • Choose Save on the left sidebar.
  • Check the box next to Embed fonts in the file.
  • Click the OK button.
  • Save the document.

Note that when saving as a PDF, make sure to go to “more options” and save as “PDF/A compliant”

To embed your fonts in Microsoft Word 2007:

  • Click the circular Office button in the upper left corner of Microsoft Word.
  • A new window will display. In the bottom right corner select Word Options . 
  • Choose Save from the left sidebar.

Using Microsoft Word on a Mac:

Microsoft Word 2008 on a Mac OS X computer will automatically embed your fonts while converting your document to a PDF file.

If you are converting to PDF using Acrobat Professional (instructions courtesy of the Graduate Thesis Office at Iowa State University):  

  • Open your document in Microsoft Word. 
  • Click on the Adobe PDF tab at the top. Select "Change Conversion Settings." 
  • Click on Advanced Settings. 
  • Click on the Fonts folder on the left side of the new window. In the lower box on the right, delete any fonts that appear in the "Never Embed" box. Then click "OK." 
  • If prompted to save these new settings, save them as "Embed all fonts." 
  • Now the Change Conversion Settings window should show "embed all fonts" in the Conversion Settings drop-down list and it should be selected. Click "OK" again. 
  • Click on the Adobe PDF link at the top again. This time select Convert to Adobe PDF. Depending on the size of your document and the speed of your computer, this process can take 1-15 minutes. 
  • After your document is converted, select the "File" tab at the top of the page. Then select "Document Properties." 
  • Click on the "Fonts" tab. Carefully check all of your fonts. They should all show "(Embedded Subset)" after the font name. 
  •  If you see "(Embedded Subset)" after all fonts, you have succeeded.

The font used in the body of the text must also be used in headers, page numbers, and footnotes. Exceptions are made only for tables and figures created with different software and inserted into the document.

Tables and figures must be placed as close as possible to their first mention in the text. They may be placed on a page with no text above or below, or they may be placed directly into the text. If a table or a figure is alone on a page (with no narrative), it should be centered within the margins on the page. Tables may take up more than one page as long as they obey all rules about margins. Tables and figures referred to in the text may not be placed at the end of the chapter or at the end of the dissertation.

  • Given the standards of the discipline, dissertations in the Department of History of Art and Architecture and the Department of Architecture, Landscape Architecture, and Urban Planning often place illustrations at the end of the dissertation.

Figure and table numbering must be continuous throughout the dissertation or by chapter (e.g., 1.1, 1.2, 2.1, 2.2, etc.). Two figures or tables cannot be designated with the same number. If you have repeating images that you need to cite more than once, label them with their number and A, B, etc. 

Headings should be placed at the top of tables. While no specific rules for the format of table headings and figure captions are required, a consistent format must be used throughout the dissertation (contact your department for style manuals appropriate to the field).

Captions should appear at the bottom of any figures. If the figure takes up the entire page, the caption should be placed alone on the preceding page, centered vertically and horizontally within the margins.

Each page receives a separate page number. When a figure or table title is on a preceding page, the second and subsequent pages of the figure or table should say, for example, “Figure 5 (Continued).” In such an instance, the list of figures or tables will list the page number containing the title. The word “figure” should be written in full (not abbreviated), and the “F” should be capitalized (e.g., Figure 5). In instances where the caption continues on a second page, the “(Continued)” notation should appear on the second and any subsequent page. The figure/table and the caption are viewed as one entity and the numbering should show correlation between all pages. Each page must include a header.

Landscape orientation figures and tables must be positioned correctly and bound at the top so that the top of the figure or table will be at the left margin. Figure and table headings/captions are placed with the same orientation as the figure or table when on the same page. When on a separate page, headings/captions are always placed in portrait orientation, regardless of the orientation of the figure or table. Page numbers are always placed as if the figure were vertical on the page.

If a graphic artist does the figures, Harvard Griffin GSAS will accept lettering done by the artist only within the figure. Figures done with software are acceptable if the figures are clear and legible. Legends and titles done by the same process as the figures will be accepted if they too are clear, legible, and run at least 10 or 12 characters per inch. Otherwise, legends and captions should be printed with the same font used in the text.

Original illustrations, photographs, and fine arts prints may be scanned and included, centered between the margins on a page with no text above or below.

Use of Third-Party Content

In addition to the student's own writing, dissertations often contain third-party content or in-copyright content owned by parties other than you, the student who authored the dissertation. The Office for Scholarly Communication recommends consulting the information below about fair use, which allows individuals to use in-copyright content, on a limited basis and for specific purposes, without seeking permission from copyright holders.

Because your dissertation will be made available for online distribution through DASH , Harvard's open-access repository, it is important that any third-party content in it may be made available in this way.

Fair Use and Copyright 

What is fair use?

Fair use is a provision in copyright law that allows the use of a certain amount of copyrighted material without seeking permission. Fair use is format- and media-agnostic. This means fair use may apply to images (including photographs, illustrations, and paintings), quoting at length from literature, videos, and music regardless of the format. 

How do I determine whether my use of an image or other third-party content in my dissertation is fair use?  

There are four factors you will need to consider when making a fair use claim.

1) For what purpose is your work going to be used?

  • Nonprofit, educational, scholarly, or research use favors fair use. Commercial, non-educational uses, often do not favor fair use.
  • A transformative use (repurposing or recontextualizing the in-copyright material) favors fair use. Examining, analyzing, and explicating the material in a meaningful way, so as to enhance a reader's understanding, strengthens your fair use argument. In other words, can you make the point in the thesis without using, for instance, an in-copyright image? Is that image necessary to your dissertation? If not, perhaps, for copyright reasons, you should not include the image.  

2) What is the nature of the work to be used?

  • Published, fact-based content favors fair use and includes scholarly analysis in published academic venues. 
  • Creative works, including artistic images, are afforded more protection under copyright, and depending on your use in light of the other factors, may be less likely to favor fair use; however, this does not preclude considerations of fair use for creative content altogether.

3) How much of the work is going to be used?  

  • Small, or less significant, amounts favor fair use. A good rule of thumb is to use only as much of the in-copyright content as necessary to serve your purpose. Can you use a thumbnail rather than a full-resolution image? Can you use a black-and-white photo instead of color? Can you quote select passages instead of including several pages of the content? These simple changes bolster your fair use of the material.

4) What potential effect on the market for that work may your use have?

  • If there is a market for licensing this exact use or type of educational material, then this weighs against fair use. If however, there would likely be no effect on the potential commercial market, or if it is not possible to obtain permission to use the work, then this favors fair use. 

For further assistance with fair use, consult the Office for Scholarly Communication's guide, Fair Use: Made for the Harvard Community and the Office of the General Counsel's Copyright and Fair Use: A Guide for the Harvard Community .

What are my options if I don’t have a strong fair use claim? 

Consider the following options if you find you cannot reasonably make a fair use claim for the content you wish to incorporate:

  • Seek permission from the copyright holder. 
  • Use openly licensed content as an alternative to the original third-party content you intended to use. Openly-licensed content grants permission up-front for reuse of in-copyright content, provided your use meets the terms of the open license.
  • Use content in the public domain, as this content is not in-copyright and is therefore free of all copyright restrictions. Whereas third-party content is owned by parties other than you, no one owns content in the public domain; everyone, therefore, has the right to use it.

For use of images in your dissertation, please consult this guide to Finding Public Domain & Creative Commons Media , which is a great resource for finding images without copyright restrictions. 

Who can help me with questions about copyright and fair use?

Contact your Copyright First Responder . Please note, Copyright First Responders assist with questions concerning copyright and fair use, but do not assist with the process of obtaining permission from copyright holders.

Pages should be assigned a number except for the Dissertation Acceptance Certificate . Preliminary pages (abstract, table of contents, list of tables, graphs, illustrations, and preface) should use small Roman numerals (i, ii, iii, iv, v, etc.). All pages must contain text or images.  

Count the title page as page i and the copyright page as page ii, but do not print page numbers on either page .

For the body of text, use Arabic numbers (1, 2, 3, 4, 5, etc.) starting with page 1 on the first page of text. Page numbers must be centered throughout the manuscript at the top or bottom. Every numbered page must be consecutively ordered, including tables, graphs, illustrations, and bibliography/index (if included); letter suffixes (such as 10a, 10b, etc.) are not allowed. It is customary not to have a page number on the page containing a chapter heading.

  • Check pagination carefully. Account for all pages.

A copy of the Dissertation Acceptance Certificate (DAC) should appear as the first page. This page should not be counted or numbered. The DAC will appear in the online version of the published dissertation. The author name and date on the DAC and title page should be the same. 

The dissertation begins with the title page; the title should be as concise as possible and should provide an accurate description of the dissertation. The author name and date on the DAC and title page should be the same. 

  • Do not print a page number on the title page. It is understood to be page  i  for counting purposes only.

A copyright notice should appear on a separate page immediately following the title page and include the copyright symbol ©, the year of first publication of the work, and the name of the author:

© [ year ] [ Author’s Name ] All rights reserved.

Alternatively, students may choose to license their work openly under a  Creative Commons  license. The author remains the copyright holder while at the same time granting up-front permission to others to read, share, and (depending on the license) adapt the work, so long as proper attribution is given. (By default, under copyright law, the author reserves all rights; under a Creative Commons license, the author reserves some rights.)

  • Do  not  print a page number on the copyright page. It is understood to be page  ii  for counting purposes only.

An abstract, numbered as page  iii , should immediately follow the copyright page and should state the problem, describe the methods and procedures used, and give the main results or conclusions of the research. The abstract will appear in the online and bound versions of the dissertation and will be published by ProQuest. There is no maximum word count for the abstract. 

  • double-spaced
  • left-justified
  • indented on the first line of each paragraph
  • The author’s name, right justified
  • The words “Dissertation Advisor:” followed by the advisor’s name, left-justified (a maximum of two advisors is allowed)
  • Title of the dissertation, centered, several lines below author and advisor

Dissertations divided into sections must contain a table of contents that lists, at minimum, the major headings in the following order:

  • Front Matter
  • Body of Text
  • Back Matter

Front matter includes (if applicable):

  • acknowledgements of help or encouragement from individuals or institutions
  • a dedication
  • a list of illustrations or tables
  • a glossary of terms
  • one or more epigraphs.

Back matter includes (if applicable):

  • bibliography
  • supplemental materials, including figures and tables
  • an index (in rare instances).

Supplemental figures and tables must be placed at the end of the dissertation in an appendix, not within or at the end of a chapter. If additional digital information (including audio, video, image, or datasets) will accompany the main body of the dissertation, it should be uploaded as a supplemental file through ProQuest ETD . Supplemental material will be available in DASH and ProQuest and preserved digitally in the Harvard University Archives.

As a matter of copyright, dissertations comprising the student's previously published works must be authorized for distribution from DASH. The guidelines in this section pertain to any previously published material that requires permission from publishers or other rightsholders before it may be distributed from DASH. Please note:

  • Authors whose publishing agreements grant the publisher exclusive rights to display, distribute, and create derivative works will need to seek the publisher's permission for nonexclusive use of the underlying works before the dissertation may be distributed from DASH.
  • Authors whose publishing agreements indicate the authors have retained the relevant nonexclusive rights to the original materials for display, distribution, and the creation of derivative works may distribute the dissertation as a whole from DASH without need for further permissions.

It is recommended that authors consult their publishing agreements directly to determine whether and to what extent they may have transferred exclusive rights under copyright. The Office for Scholarly Communication (OSC) is available to help the author determine whether she has retained the necessary rights or requires permission. Please note, however, the Office of Scholarly Communication is not able to assist with the permissions process itself.

  • Missing Dissertation Acceptance Certificate.  The first page of the PDF dissertation file should be a scanned copy of the Dissertation Acceptance Certificate (DAC). This page should not be counted or numbered as a part of the dissertation pagination.
  • Conflicts Between the DAC and the Title Page.  The DAC and the dissertation title page must match exactly, meaning that the author name and the title on the title page must match that on the DAC. If you use your full middle name or just an initial on one document, it must be the same on the other document.  
  • Abstract Formatting Errors. The advisor name should be left-justified, and the author's name should be right-justified. Up to two advisor names are allowed. The Abstract should be double spaced and include the page title “Abstract,” as well as the page number “iii.” There is no maximum word count for the abstract. 
  •  The front matter should be numbered using Roman numerals (iii, iv, v, …). The title page and the copyright page should be counted but not numbered. The first printed page number should appear on the Abstract page (iii). 
  • The body of the dissertation should be numbered using Arabic numbers (1, 2, 3, …). The first page of the body of the text should begin with page 1. Pagination may not continue from the front matter. 
  • All page numbers should be centered either at the top or the bottom of the page.
  • Figures and tables Figures and tables must be placed within the text, as close to their first mention as possible. Figures and tables that span more than one page must be labeled on each page. Any second and subsequent page of the figure/table must include the “(Continued)” notation. This applies to figure captions as well as images. Each page of a figure/table must be accounted for and appropriately labeled. All figures/tables must have a unique number. They may not repeat within the dissertation.
  • Any figures/tables placed in a horizontal orientation must be placed with the top of the figure/ table on the left-hand side. The top of the figure/table should be aligned with the spine of the dissertation when it is bound. 
  • Page numbers must be placed in the same location on all pages of the dissertation, centered, at the bottom or top of the page. Page numbers may not appear under the table/ figure.
  • Supplemental Figures and Tables. Supplemental figures and tables must be placed at the back of the dissertation in an appendix. They should not be placed at the back of the chapter. 
  • Permission Letters Copyright. permission letters must be uploaded as a supplemental file, titled ‘do_not_publish_permission_letters,” within the dissertation submission tool.
  •  DAC Attachment. The signed Dissertation Acceptance Certificate must additionally be uploaded as a document in the "Administrative Documents" section when submitting in Proquest ETD . Dissertation submission is not complete until all documents have been received and accepted.
  • Overall Formatting. The entire document should be checked after all revisions, and before submitting online, to spot any inconsistencies or PDF conversion glitches.
  • You can view dissertations successfully published from your department in DASH . This is a great place to check for specific formatting and area-specific conventions.
  • Contact the  Office of Student Affairs  with further questions.

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Academia Insider

How long is a PhD dissertation? [Data by field]

The final piece of the PhD journey is the PhD dissertation. It takes many years to accumulate enough original and new data to fill out a dissertation to the satisfaction of experts in your field. Interestingly, the PhD dissertation length and content vary significantly based on the field you are studying and the publishing conventions.

A PhD can be anywhere from 50 pages to over 450 pages long. This equates to between about 20,000 words to 100,000 words. Most PhD theses are between 60,000 and 80,000 words long excluding contents, citations and references.

A PhD thesis contains different sections including an introduction, methods, results and discussion, conclusions, further work, and references. Each one of these different sections will vary in length depending on the field of study and your particular topic.

Ultimately, a PhD dissertation should contain as many pages and words as it takes to communicate the results of your multi-year investigation.

It is very rewarding to see your thesis come together as you are writing day after day. When I was writing my PhD dissertation I wrote the sections separately and my heart filled with joy when I finally put them all together and compile them into a single PDF document.

Counting the pages should not be the way to determine a PhD dissertation’s value but it certainly helps when your thesis is starting to look substantial in thickness.

How many pages should a PhD dissertation be?

A PhD dissertation should contain as many pages and words as it takes to outline the current state of your field and provide adequate background information, present your results, and provide confidence in your conclusions. A PhD dissertation will also contain figures, graphs, schematics, and other large pictorial items that can easily inflate the page count.

Here is a boxplot summary of many different fields of study and the number of pages of a typical PhD dissertation in the field. It has been created by Marcus Beck from all of the dissertations at the University of Minnesota.

how many references should a phd thesis have

Typically, the mathematical sciences, economics, and biostatistics theses and dissertations tend to be shorter because they rely on mathematical formulas to provide proof of their results rather than diagrams and long explanations.

On the other end of the scale, English, communication studies, political science, history and anthropology are often the largest theses in terms of pages and word count because of the number of words it takes to provide proof and depth of their results.

At the end of the day, it is important that your thesis gets signed off by your review committee and other experts in the field. Your supervisor will be the main judge of whether or not your dissertation is capable of satisfying the requirements of a PhD in your field.

If you want to know more about how long a Masters’s thesis and PhD dissertation is you can check out my other articles:

  • How Long is a Masters Thesis? [Your writing guide]
  • How long is a Thesis or dissertation? [the data]

Can a PhD dissertation be too long?

A PhD thesis should contain enough evidence and discussion to report on the most significant findings of your PhD research.

A PhD dissertation should not contain everything that you have done during your PhD. It should only include the data and information required to convince your PhD examining body that wraps up and tells the full story of particular lines of investigation.

Including random results, thoughts, or superfluous explanation can result in a dissertation that is unfocused. I have heard of music PhD is being described as too verbose and physical sciences PhD dissertations as being unfocused.

Therefore, a PhD thesis can be too long if the information it contains does not form a full and cohesive story.

One of my colleagues during their PhD removed an entire chapter from the thesis after writing it as the supervisor said that it needed more experiments to be a full story. They did not want to spend the next six months gathering the data and simply removed the chapter altogether.

How short can PhD dissertation be?

The shortest PhD dissertations are typically found in mathematics.

George Bernard Danzig was an American mathematical scientist who made contributions to industrial engineering and many other mathematical-related fields. An interesting miscommunication led to 1 of the shortest PhD theses ever.

In 1939 his professor wrote two problems on the blackboard and Danzig thought they were homeless assignments. He stated that they were harder than usual but handed in solutions to the surprise of the professor.

They were, in fact, open mathematical problems in statistics.

His professor said to bind the solution to the two problems together and submit them as his thesis – the total thesis length = 14 pages.

Obviously, most PhD theses and dissertations will be so much longer than that!

My PhD dissertation was 256 pages long. It was full of schematics, diagrams, and tables to demonstrate and communicate my findings.

I would say that most people’s PhD thesis experience will be closer to mine than Prof George Bernard Danzig’s.

Why PhD dissertations are typically so long

PhD dissertations are often over 200 pages long.

One of the primary reasons they are so long is that it is a single document that summarises many years of hard work. Also, summarising the research field to date and making sure that all of your references and citations are included so you avoid plagiarism will bolster the word count of the thesis dramatically.

Here are all of the reasons PhD dissertations tend to be so long.

Many years of work

PhD theses or dissertations contain many years of research and analysis.

In many of my YouTube videos I recommend that a PhD student work towards their PhD thesis by doing at least three hours of focused work every work day.

This amount of work quickly adds up.

Of course, not every bit of work makes it into the PhD dissertation but a lot of it does. It can be difficult to work out what to include or leave out of your thesis.

As a PhD student, I perfected the art of turning one experiment into many different types of grafts and schematics to fully explore the limits of my data. The graphs can take up a lot of space in your PhD thesis and, therefore, bolster the page count significantly.

In depth literature review

One of the most substantial parts of a PhD dissertation is the literature review.

The literature review can take up a huge portion of the early part of your PhD dissertation depending on the amount of data and publications in your field.

Writing an in-depth literature review requires just as much meticulous data analysis and searching as the central part of your dissertation.

Figures and schematics

Some fields end up producing a lot of figures and schematics.

My thesis had many full-page figures of atomic force microscopy experiments with much more explanation on subsequent pages.

how many references should a phd thesis have

As they say, a picture paints a thousand words and a dissertation can really benefit from having many schematics to highlight the important aspects of your findings.

References and citations

The recommended PhD dissertation word count from an institution or university does not include citations, references, or other thesis parts such as summary of abbreviations, table of figures, et cetera.

However, these components of your dissertation can take up many pages and add to the overall thickness of your PhD dissertation.

University formatting rules

University formatting rules will also dictate how you many pages your words take up.

I often get roasted on my YouTube channel for having doublespaced lines and wide margins. Unfortunately, this layout was dictated by my university before printing.

PhD dissertations often end up going into long-term storage and therefore, need to adhere to archival and standardised formatting rules.

Deep in the depths of the University of Newcastle, there is a copy of my thesis on a shelf. The formatting and binding rules mean that my thesis looks like everyone else’s.

Universities will often have their own requirements for PhD dissertation cover colour, quality, and type of paper. Even the quality of the paper can change the thickness of the PhD dissertation significantly.

PhD by publication

It is becoming increasingly common to submit a number of peer-reviewed papers bound together with supplementary information in between instead of a PhD dissertation.

The benefits of this to the researcher and university are:

  • More early career peer-reviewed journals for career advancement
  • an easier review process – they have already been peer-reviewed
  • an early focus on publishing means better research outcomes for the researcher, supervisor, and Department.
  • No mad rush at the end to finish a thesis
  • continually writing peer-reviewed papers throughout your PhD helps with timely analysis and communication of results

Even though this option has been available to PhD students for a number of years, I have only known a handful of students actually submit their PhD via publication.

Nonetheless, having this option will suit some research fields better than others and lead to a more productive PhD.

Wrapping up

This article has been through everything you need to know about the length of a PhD dissertation and the common lengths of PhD dissertations for various fields.

Ultimately, there is no predefined length of a PhD.

A PhD thesis is as long as it needs to be to convince your examiners that you have contributed significantly enough to an academic field to be awarded the title of Dr of philosophy.

Mathematical and analytical theses tend to be shorter and can be as short as 50 pages (with one of the shortest being only 14 pages long). At the other end of the spectrum, PhD students in anthropology and history tend to produce the longest dissertations.

how many references should a phd thesis have

Dr Andrew Stapleton has a Masters and PhD in Chemistry from the UK and Australia. He has many years of research experience and has worked as a Postdoctoral Fellow and Associate at a number of Universities. Although having secured funding for his own research, he left academia to help others with his YouTube channel all about the inner workings of academia and how to make it work for you.

Thank you for visiting Academia Insider.

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how many references should a phd thesis have

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COMMENTS

  1. citations

    Rather, they should be that springboard that get them produce more than what they get as intake. Numerically, I expect to have each single reference to be equated with two pages of the candidate's work as a maximum. This would mean that a dissertation of 300 pages should not have used more than150 references.

  2. Tips for writing a PhD dissertation: FAQs answered

    A PhD thesis (or dissertation) is typically 60,000 to 120,000 words ( 100 to 300 pages in length) organised into chapters, divisions and subdivisions (with roughly 10,000 words per chapter) - from introduction (with clear aims and objectives) to conclusion. The structure of a dissertation will vary depending on discipline (humanities, social ...

  3. How to write a PhD thesis: a step-by-step guide

    It often starts with "But", "Yet" or "However". The third sentence says what specific research has been done. This often starts with "This research" or "I report…". The fourth sentence reports the results. Don't try to be too tricky here, just start with something like: "This study shows," or "Analysis of the data ...

  4. A Guide to Writing a PhD Thesis

    How long is a PhD thesis? The length of a PhD thesis varies from subject to subject, but all are far longer than those for undergraduate or Masters degrees. Your university will usually set an upper limit - typically between 70,000 and 100,000 words, with most dissertations coming in at around 80,000 words.

  5. APA: how to cite a PhD thesis [Update 2023]

    How to cite a PhD thesis in APA. If the thesis is available from a database, archive or any online platform use the following template: Author (s) of the thesis: Give the last name and initials (e. g. Watson, J. D.) of up to 20 authors with the last name preceded by an ampersand (&). For 21 or more authors include the first 19 names followed by ...

  6. How Many References in a Research Paper?

    According to Milojević's study encompassing research in the fields of astronomy, mathematics, robotics, ecology, and economics, the highest and average number of references per article page were as follows: Ecology: highest, ~58; average reference per page, 6; Math and robotics: highest, ~28; average reference per page, <1; and.

  7. How many references should I have?

    Use as many references as you need. You'll need an appropriate amount for your academic level - this will vary. Reference everything you cite. If you use an idea, cite and reference it. Ask your tutor. They may have guidance for you on how much reading they expect you to do.

  8. What Is a Dissertation?

    A dissertation is a long-form piece of academic writing based on original research conducted by you. It is usually submitted as the final step in order to finish a PhD program. Your dissertation is probably the longest piece of writing you've ever completed. It requires solid research, writing, and analysis skills, and it can be intimidating ...

  9. Choosing References for a PhD Application

    Choosing References for a PhD Application. As part of your application for doctoral study you may be asked to provide up to three academic referees. The references they provide can make or break your PhD application and are essential to giving you the best chance of being successful. You should therefore think carefully about who your referees ...

  10. How to cite a PhD thesis in Harvard

    To cite a PhD thesis in a reference entry in Harvard style include the following elements: Author (s) of the PhD thesis: Give the last name and initials (e. g. Watson, J.) of up to three authors with the last name preceded by 'and'. For four authors or more include the first name followed by et al., unless your institution requires referencing ...

  11. In-Text References, Footnotes, Endnotes, Tables & Figures in PhD Theses

    1.2.6 In-Text References, Footnotes and/or Endnotes. References to the sources cited and/or quoted in a thesis should appear throughout the thesis. Depending on the discipline, university and department guidelines and the requirements of the individual thesis, in-text citations may take the form of numerical references, be based on the last ...

  12. PDF A Guide to Writing your PhD Proposal

    Therefore, in a good research proposal you will need to demonstrate two main things: 1. that you are capable of independent critical thinking and analysis. 2. that you are capable of communicating your ideas clearly. Applying for a PhD is like applying for a job, you are not applying for a taught programme.

  13. How Many References Should a Research Paper Have? Study of 96,685

    Here's a summary of the key findings. 1- The average number of references for a research paper is 45, with 90% of research papers having between 8 and 102 references. However, this number depends a lot on study design. For instance, a systematic review typically has 49 references while a case report has only 24.

  14. Bibliography or References

    There is no reference style required by the Graduate College Thesis Office. However, departments may require the use of a reference style that is appropriate to the student's program of study. All theses are required to have either a bibliography or a list of references. When placed at or near the end of a thesis, the references section is ...

  15. Guides and databases: Harvard: Thesis or dissertation

    Thesis or dissertation. To be made up of: Author. Year of submission (in round brackets). Title of thesis (in italics). Degree statement. Degree-awarding body. Available at: URL. (Accessed: date).

  16. Number of references in a PhD thesis?

    E. Eppi 132 posts. I'm qualitative and, doing a rough calculation, my final thesis has around 280 references - so less than you! Now I hope I have enough!! 16 years ago. A. Away 78 posts. I'm doing an computer science PhD and my institution has a maximum of 50000 words (as opposed for 80000 for humanities).

  17. Writing a Literature Review

    In a PhD thesis, the literature review typically comprises one chapter (perhaps 8-10,000 words), for a Masters dissertation it may be around 2-3,000 words, and for an undergraduate dissertation it may be no more than 2,000 words. In each case the word count can vary depending on a range of factors and it is always best, if in doubt, to ask your ...

  18. How Long Is a PhD Thesis?

    Unfortunately, there's no one size fits all answer to this question. However, from the analysis of over 100 PhD theses, the average thesis length is between 80,000 and 100,000 words. A further analysis of 1000 PhD thesis shows the average number of pages to be 204. In reality, the actual word count for each PhD thesis will depend on the ...

  19. Q: What is the standard number of references a paper should have?

    Answer: Regarding the number of reference citations, there is no specific number or range that is considered as normal or standard. You should cite just about enough sources that are required for your paper. The number of references you will use depends on how much literature exists on the topic. If you are working on a very new and original ...

  20. Formatting Your Dissertation

    Depending on the size of your document and the speed of your computer, this process can take 1-15 minutes. After your document is converted, select the "File" tab at the top of the page. Then select "Document Properties." Click on the "Fonts" tab. Carefully check all of your fonts.

  21. How many references did you have? : r/PhD

    A normal article usually has 30 - 50 references. A review article I'm currently working on has 141 references so far. The dissertation will consist of 3 - 5 articles depending on how many are needed for a clear contribution. Plus, intro, methods and conclusions chapter. 2.

  22. How long is a PhD dissertation? [Data by field]

    A PhD can be anywhere from 50 pages to over 450 pages long. This equates to between about 20,000 words to 100,000 words. Most PhD theses are between 60,000 and 80,000 words long excluding contents, citations and references. A PhD thesis contains different sections including an introduction, methods, results and discussion, conclusions, further ...

  23. How to Write a PhD Thesis: A Step-by-Step Guide for Success

    Step 1: Understand the Requirements. The initial step in crafting your PhD thesis is to thoroughly understand its specific requirements, which can vary widely between disciplines and institutions. A thesis must contribute new knowledge to its field, necessitating a deep familiarity with the expected structure, depth of analysis, and submission ...

  24. How Many References You Should Have In Your PhD Thesis; I ...

    I had 169 references listed in my thesis (*NOT* 263 that I mention in the video - apologies) and I have heard a librarian say you should consult 1000 in tota...