Sometimes we may ask questions on stack exchange or online forums wherein the response is helpful or even essential to a piece of work that gets published in an academic journal. If this occurs, how should credit be given to those involved in the exchange? Should they all be included as authors? Should a link to the forum be included as a reference in the paper?

Once something is in a stack exchange or forum, it's "published". Perhaps in the future, the current peer review model will transform into people writing blogs and posting in forums and databases. But for now, how might this issue be dealt with while forums, blogs, etc coexist with journals?

  • 15
    This issue has come up on CS Theory StackExchange; the most popular recommendation is to copy the BibTeX that MathOverflow generates when you click on a "cite" link. Several questions and answers from both of those sites have been cited in journal articles.
    – JeffE
    May 16, 2012 at 13:19
  • 1
    @JeffE Many thanks for the reference. I suspected that this sort of question might have come up in other places but it was sufficiently difficult for me to find that I thought it was worth posting another question here. I think that, as I have seen mentioned in some of the answers below, the way in which the issues I've raised are dealt with vary significantly by field so it is good to know how they might be dealt with in computer science. May 17, 2012 at 0:36
  • 1
    @EnergyNumbers I think I understand your perspective on the second paragraph, but the first part of the question scratches the surface of a deeper issue the way I see it. If it is a rant (...written in a wild, impassioned way), then it is one I expect to resonate to some degree with others. I think the political aspects of science are real and should not be swept under the rug in discussion. What I will do is remove what is less relevant to the question and post some of my comments as an answer. May 17, 2012 at 0:57
  • @EnergyNumbers Here's one reference for the debate about whether or not Stack Exchange is considered to be a forum. May 17, 2012 at 2:58
  • @JeffE it's nice to know that journal articles cited several articles from MO and CS Theory, are you able to give any example that was picked up by Google Scholar? i.e. Google Scholar shows that a Stack Exchage post got cited significantly? May 8, 2020 at 19:54

4 Answers 4


Issue of citing authorship

Starting from first principles, I think in most instances on StackExchange it would be the original poster of the quoted answer that would be the relevant author. The person asking the question is useful but it is typically the information provided in a particular answer that would be the typical candidate for citation.

That said, I imagine there could be instances where the question itself or an overall exchange represents the unit of citation. In such a case, it would make sense to cite all relevant contributors.

Does something learnt from StackExchange need to be cited?

A lot of learning goes into a journal article. This learning comes from many sources. That which gets cited is only a small fraction of that. A scientist might (a) read a statistics book; (b) ask a friend; or (c) ask a question on Stats.StackExchange.com to learn more about how to analyse his or her data. In both cases, the person has devised an analysis plan based on having learnt something. However, generally these sources are not cited. In each case the scientist has learnt how to do something, but ultimately the knowledge is already established in the literature.

I also think that the vast majority of posts on StackExchange do not constitute a citable unit of original research. That said, where this does occur and it it influences your work, it makes sense to cite the source.

  • 14
    cstheory regularly generates original proofs (although we are not too great at keeping track of these), some of them out-performing the best in the literature, I assume the same happens over at MO. If you did learn something important from SE, even if it is not citable, I feel that you should mention it in your acknowledgement just as you would if a colleague gave important suggestions during a coffee break. May 16, 2012 at 15:26
  • 3
    Yes, something learnt from StackExchange needs to be cited, just as "something learnt" from a journal article needs to be cited.
    – JeffE
    Apr 14, 2018 at 17:31
  • 3
    @JeffE If part of my result was learned on StackExchange, yes. If I learned on StackExchange what abbreviation X means or how to use my statistics software, no.
    – sgf
    Apr 15, 2018 at 0:27

Citing a forum post is very close to "personal communications".

The benefit of actually citing (instead of thanking the author in the acknowledgements) is that you:

  • explicitly say what was their contribution,
  • give more details or provide the context
    (sometimes the post is longer, with more threads than those mentioned in the paper),
  • implicitly build visibility or prestige of the forum/SE site/MO/...

When it comes to the author(s), there is no established approach. Typically (default from cite on the MathOverflow and link -> cite on the StackExchange) you cite the exact post (e.g. the selected answer with its author). However, if you want to point explicitly to more authors (e.g. actually you base on two answers or the question itself is non-trivial), then it may be a good idea to include them as well.

If you consider that their contribution is substantial, then you can decide to have them as coauthors (of course assuming they agree). But then the rules are no different from talking in person. (Except for the fact, that on fora some people may be unreachable).

Moreover, if something is simple (but not trivial, i.e. present in standard textbooks), citation is welcome. For that reason people quote tables of integrals and for the same reason I think that simple findings you base on should be cited as well.

I think that hiding one's sources is neither productive nor fair.


What merits a citation or coauthorship is a subtle question, but the answer doesn't change when people interact online. The main difference is that the interaction is more visible: authors may feel awkward if they decline to cite a publicly visible (but unimportant) contribution, and the contributor may feel encouraged to complain. This adds to the pressure of the decision, but it shouldn't change the answer, and the other issues and subtleties are the same as in offline interaction.

As for online contributions being "published", I suppose that's true in the technical sense that they have been made available to the public, but that's not what academics mean when they talk about publication. For example, listing a stackexchange answer as a publication on one's CV would be considered at least eccentric, if not deceptive, regardless of how impressive the answer was. (The best one could hope for is to list it somewhere else.)

I'm not sure what the relevance of the second paragraph of the question is, but here's a guess. Suppose Alice is writing a paper and Bob makes an absolutely critical intellectual contribution via a stackexchange answer. Normally such a contribution would merit coauthorship, but Alice might declare that Bob's work is already published via stackexchange and that she will simply cite it rather than making him an author. That would be unreasonable and unfair to Bob, but if Alice was scrupulous in citing Bob's answer and giving him full credit for its contents, then it's not clear that Bob would have any recourse. I'm not convinced this is more than a theoretical problem, since the number of stackexchange answers that could merit coauthorship is tiny (maybe not zero, but that's a good first approximation) and most authors are well behaved anyway. However, I suppose it could happen.


There's a simple test for citing/acknowledging. Did you come up with the contribution yourself ? If not, then you need to cite whoever did.

Whether this amounts to authorship, and how exactly to cite the contribution (as a footnote, acknowledgement, personal contribution or whatever), depends on the conventions of your research area (especially for authorship thresholds). In general, if you're merely deciding between different kinds of citation, more information is usually better.

As for the entire second paragraph about conventions in publishing, I think that's irrelevant.

  • Naming a contribution in the acknowledgement section is not citing. There's a fundamental difference between that.
    – MERose
    Mar 2, 2015 at 15:30
  • 3
    Your first paragraph is misleading, because it seems to imply that the reverse implication holds, too (if I came up with something myself, I don't need a reference). However, if I come up with a contribution myself and then I find out that it's a known result, good practice demands that I add a reference. Aug 10, 2018 at 4:50

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .