I'm aware that some institutions offer something that is called 'Thesis by Publication' (sandwich thesis) but that's not available to me. I'm trying to work out what pitfalls there may be to simply copying from papers that I have previously published in order to form large sections of my thesis.

The papers that I've published were largely designed to solve major problems encountered within the larger frame of research, so altogether they should follow a single coherent line of thought.

Must one's own work be cited in a thesis? This would be standard when submitting a paper for publication, but there is a stipulation when publishing papers that that work has not been already published elsewhere, and the same sort of thing does not really crop up with a thesis, does it?

Are there any other potentially pitfalls in this course of action?

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    Yo0u should definitely be talking to your advisor... – Solar Mike Apr 14 '19 at 8:50
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    I did something like this --- I took my published (and submitted) papers and put them together to tell a story (well, a significantly expanded story, but still). Long parts of text were copied almost vanilla from the papers. I did make sure to point out what and where from I am borrowing in the introduction to the thesis and in the chapter introduction, and for each main result, I have added a citation to the paper where it first appeared (if at all). My field is math, and I imagine it would be okay in math anywhere, but you really should find out form colleagues/advisors in your dpt anyway. – tomasz Apr 14 '19 at 12:44
  • Oh, one thing of note: in my department, it was customary for the coauthors (or at least the advisor) to write (confidential) short notes describing how much you contributed to each paper. – tomasz Apr 14 '19 at 12:46
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    Some universities require that a thesis be new nonpublished results (silly, I know), some allow sandwich theses, some don't, ... The point is you really need to check your university/department guidelines. – Kimball Apr 14 '19 at 13:00
  • "(sandwich thesis) but that's not available to me." Wherever this rule is written down, the answer to your question will also be written down. It's a matter of your university's policy, not something decided by votes on academia.SE. – David Ketcheson Apr 15 '19 at 3:03

A general answer for this problem can not be given here with 100%. Here some hints:

The problem you might be running in is called self plagiarism and different institutions allow/forbid different approaches here. If you are planning to write the thesis like this (which is absolutely your right) then:

  1. It is essential for you to get the guidelines of your university before starting to write (and save them somewhere where you will still be able to find them even years later)
  2. Check the policy of the journals that you have published in - most journals allow to re-use published material in your thesis but make sure to also print out these guidelines and keep them.

Checking with the university and the journals (and to have written proof of it!) might save you many troubles later. Because if someone later claims that you commited self plagiarism then you can always cite the official guidelines that were in place at the time when you wrote your thesis.

You should also check with your supervisor but just having his/her oral Ok might not be enough many years later.

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    Self-plagiarism would be a potential problem if (and only if) the university does not allow already published results to be counted for the thesis. What I've met so far is that material already used for other exams (e.g. Master thesis) is not allowed. Point 2 (which applies regardless of which material this particular university allows) is about copyright infringement. – cbeleites unhappy with SX Apr 14 '19 at 14:34
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    I'd emphasize those documented school guidelines are the most important factor in this answer. They are probably in some kind of "thesis handbook" or "manual" the school provides, which every student needs to read carefully before writing their thesis. Otherwise it will probably not be accepted. My school required we meet with a librarian I believe, to go over in detail. – A Simple Algorithm Apr 14 '19 at 20:19
  • @cbeleites I haven't come across anywhere that wouldn't let you use results obtained during your studies for a degree in that degree's thesis, published or otherwise. Somewhat defeats the point of publishing during that time, which is something they tend to want to encourage. If the words are your own (i.e. not from another author), then I highly doubt you'll run into issues other than perhaps rarely copyright-related ones - though do check. – Dan Apr 15 '19 at 9:58
  • @Dan, It might be a problem even if the words are your own. Therefore get the university guidelines so that you can easily defend yourself in case someone makes accusation 10 years later. See also my answer here for what is plagiarism (that same applies for self-plagiarism): academia.stackexchange.com/questions/127858/… – lordy Apr 15 '19 at 10:05
  • @Dan: as I said in my answer, I'd consider it highly unusual (not to say flawed) to formulate the novelty requirements in a way that precludes publication. (And I'd recommend not to attend any such program) That being said, the only thing that counts are the rules of the univeristy in question. (To me it's similar to journals that consider a draft on arXiv a prior publication that makes any submission of that manuscript to them lacking novelty and thus unacceptable. Doesn't make sense, isn't good, but does exist) – cbeleites unhappy with SX Apr 15 '19 at 10:09

Others have already told you that a university can require novelty for a thesis in the sense that results published as papers do not count towards the thesis work.

However, the setting I've seen more often is that publication as paper (or conference presentation, poster, etc.) do not hurt the thesis novelty requirement but that no material that has been submitted for any other exam (e.g. Master thesis) can be used for the exam/thesis in question. I'll answer for this scenario.

Must one's own work be cited in a thesis?

  • In consequence of that novelty requirement, any material that was submitted for other exams has to be cited as such (i.e. like any other citation) - otherwise it would be self-plagiarism.
  • OTOH, having peer-reviewed publications of the thesis material would usually count in your favor, so it is in your best interest to cite them as such even if is your own thesis work ("The results of this section have been published as [publication]").
    In my (long form, but other language) thesis I numbered my publications with a prefix to mark them, and put them also in a separate reference list (the thesis application anyways required a list of my publications).
  • Publications of the thesis work where you have co-authors must be cited unless you manage to leave out the contributions of your coauthors in the long-form thesis.

pitfalls there may be to simply copying from papers that I have previously published in order to form large sections of my thesis.

The remaining pitfall then is copyright of the paper.

  • If you retained copyright for the paper, you're fine with reusing from the publisher's point of view.
  • Many journals that require you to sign over copyright to them do allow thesis use in that license contract. Others require you to obtain a license (usually highly automated process). All this is pretty streamlined nowadays because it's neede for the boilerplate theses.
    => read the copyright agreements and act accordingly
  • Also your legislation may say that you retain certain rights (i.e. clauses in the copyright agreement that take those rights away are void).
  • Worst case (you don't have a license to reproduce the required parts of the paper), you'll have to reword the content of the paper and to re-format tables and figures.
    I'd consider a publisher with such terms a legitimate reason to not publish there any thesis-relevant work.
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    For the second part of your answer: Nowadays it's pretty easy to get a reuse permission from many publishers, it's even free (which was not always the case earlier). – Oleg Lobachev Apr 14 '19 at 16:31
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    With regards to copyright, this also depends on the local copyright laws. For example under UK law, you have the right to submit copyrighted material for examinations without needing permission (although if the thesis is otherwise deposited or distributed you may need it) – Bobgom Apr 14 '19 at 17:06

What I have seen is:

  • to state in the first paragraph of a chapter / section, that this chapter / section was already published as a paper, your paper, and you properly cite it.
  • You don't make a verbatim copy, but you can lead closely to the paper. Often you want to give more details in a PhD thesis compared to a paper, so it is less difficult than it may sound.

This does only work, if you wrote the paper. Otherwise you are almost-copying someone's else work, which is wrong.
If you intend to follow this idea, ask your adviser whether it is ok.


Actually, I will give a general answer. Don't do this. It is clearly self plagiarism and this is antithetical to the scholarly process.

Ordinary plagiarism is normally stated as attributing to yourself the work of others, but there is another aspect of it that becomes clearer when you consider self plagiarism.

When anyone reads a scholarly work, unless it is completely self contained, they will want to know where the various ideas in it originated. The way to do this is to cite the previous work. What this allows is that the reader is able to go to the prior work and read the arguments there, including further citations. S/he is then able to both understand and evaluate the complete development of the ideas in the paper that started the investigation.

If you self plagiarize, unless you copy the work as a whole, including the citations and references, you break this chain. It becomes more difficult for a serious researcher to put together the bigger picture.

It is easier now, but when I was a math grad student half a century ago, one spent hours in the library reading and trying to understand deep concepts. Usually they were too difficult for us beginners, so we went back to the referenced articles to get a bigger picture. Eventually our understanding emerged and we could then work forward back to the starting point. You, in this century, don't need to do it in consultation with the librarian any more, but the process remains the same. It is the citations that form the fundamental context of a work, not just the words in the work itself.

So, even if you advisor says it is fine, and even if local custom says it is fine, it is not fine. Your thesis will become a block if anyone stumbles across it. It will be a wall, when it should be a doorway.

However, if you still hold copyright to your original papers, it is permissible to quote from them extensively. But still necessary to cite the quotations, rather than giving the impression that the ideas originated in this work, rather than in prior works, each with their own full context.

That context is fundamentally important. Don't subvert the scholarly process.

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    Are theses actually published? Aren't theses just really for the examination of awarding a PhD (or Masters)? Maybe it depends on the discipline. – Stumbler Apr 14 '19 at 14:06
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    This is a baffling answer. It seems to me that a thesis is a perfect place to rewrite a connected series of papers that you have published, clarifying the ideas in them, making it is a self-contained work including all the logical arguments, so that the reader doesn't have to go find the original papers and read them. (Of course, you should say which parts came from previous papers.) Why make the readers look at the original papers if you don't have to? Is it good for their souls? – Peter Shor Apr 14 '19 at 15:38
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    @PeterShor, as I said, you can quote large sections safely in the absence of other restrictions. But don't present the work as new when it is not. You don't need to paraphrase. You just need to be honest about origins. I'm surprised that isn't clear. – Buffy Apr 14 '19 at 17:36
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    @PeterShor My reading of the question is that the asker intends writing their thesis as if the papers don't exist: using the material from them but not citing them. At first, I thought "Don't do this" meant don't copy-paste stuff from your papers but I think it actually means don't do it without saying you've done it. – David Richerby Apr 14 '19 at 18:13
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    Buffy, I'm along with @PeterShor: all citations in the paper also need to appear in the thesis (by the same logic by which they made it into the paper) - so I don't see how the citation chain could be broken unless there's proper plagiarism. And I'd expect a thesis to be more detailed and elaborate than the paper, not the other way round - so for learning on the topic, a long-form thesis (or a technical report) is usually much better than the paper. – cbeleites unhappy with SX Apr 14 '19 at 18:16

'Thesis by Publication' ... is not available to me.

Perhaps not as such, but I very much doubt your institution wants your thesis to be on different research than what you've published. I would guess that the university expects you to do more than simple copy-paste-bind-together. However, the most important advice I have to give you is:

  1. Read your university and your faculty/departments specific, detailed guidelines on what you're supposed to write and submit.
  2. Talk to your advisor - s/he knows what is expected from the experience of previous advisees.
  3. Skim through theses of previous advisees of your advisor or others in the department, whose research you're somewhat familiar with. See how their published papers relate to the thesis.

what pitfalls there may be to simply copying from papers that I have previously published

Don't "simply copy", but rather adapt: Use common preliminaries for different results; weave more of the context of the work in the other papers into the exposition of each result; mix up the section structure somewhat; etc.

Must one's own work be cited in a thesis?

Well, essentially yes, but even there are caveats here - never mind them. Just say explicitly that "this section/chapter is mostly based on [SelfRefHereToThePaper]" (or however it is customary to self-reference in theses in your university". That also means that if anybody has a unforeseen problem with this being the case, they'll complain upfront rather than accuse you of anything underhanded.


It is a positive that your work has already gone through peer review and is archived.

Yes, cite the previous articles (and retain the original citations from those articles). I would also discuss it in your intro chapter. You will probably have a subsection of the intro called "organization of the thesis". You can have some structure like:

Para one (list and describe the chapters in content, organization. Show a heirarchical structure and a reason for the ordering.)

Para two: Chapters 4, 5 and 7 are original work from this thesis research which were successfully published during the study. (citations). Chapters 6 and 8 are intended to be reworked and published in the future as stand-alone journal articles. Chapters 1 and 2 include synthesized content from the published research reports as well as expanded detail for this thesis. Chapter 3 is a synthesis of issue X of the lab work from articles corresponding to chapters 4, 5, and 6. It is intended to be published as a standalone article in a journal contentrating on issue X

I would go ahead and do some light editing to make the thing more integrated. For example in experimental work, the methods sections for the lab work will have a fair amount of partial duplication. Separating that out to a chapter 2 on "methods" can be useful. Same issue for the intro sections, excise them and combine into a more integrated/expanded section within the Intro chapter that has lit review and motivation.

You may, may not have other reasons to reorganize some of the meat of the content. I would not strain to do so, just do so if it makes editorial sense, not through some desire to change things for appearance.

This is also a good chance to add some expanded content that you feel is helpful but were unable to put into terse journal articles. E.g. details/advice on methods, apparatus, safety. Work that was non-notable for an article (e.g. a computer-based calculation that agrees with earlier direct methods, properties experiments that showed no change in output but may be useful in the future for example in comparison to systems with more interesting results, more detailed simulations, verification of terse proofs/derivations in supporting papers, etc. You should have a little bit the attitude that this thesis may be looked at by follow-on students, postdocs, or even your PI when doing followon work. It can be a helpful training document. This is a bit of a different issue than the archived literature (which serves that function also, but tends to be more terse.)

Also, it is just a chance to record things that you don't want "lost". I am an advocate of "publish everything", but still we have to live with the reality of terseness in normal science articles. Best is to find some way to get every finding, idea into regular journal articles. But the thesis is a sort of "half a loaf" versus just never getting the content recorded at all. The rationale for getting content published is that it prevents rework (which happens too much, see the E Bright Wilson book on research.)

IANAL but I think it is extremely unlikely that journals will have an issue with the republication of content (even graphs and the like) within a student thesis. Or the converse, when the content was in the thesis first.

Nor are your actions unethical. (I disagree with the surfeit of caution in the Buffy reply.) It is very normal in the sciences for a thesis to be a collection of papers. Not the European explicit sandwich. But a lightly edited smorgasbord, sure. Nobody is surprised, bewildered or aghast at this. It is a positive that you already got papers done.

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