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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeFeb 21st 2021
   • (edited Feb 21st 2021)
   • PermaLink
   Author: Urs
   Format: MarkdownItexa bare list of historical references, prompted by what Dmitri started [here](https://nforum.ncatlab.org/discussion/391/cohomology/?Focus=89869#Comment_89869), to be `!include`-ed into the lists of references of relevant entries, such as at _[[cohomology]]_, _[[cochain cohomology]]_, _[[singular cohomology]]_, _[[cellular cohomology]]_ and probably elsewhere, too <a href="https://ncatlab.org/nlab/revision/cohomology+--+early+references/1">v1</a>, <a href="https://ncatlab.org/nlab/show/cohomology+--+early+references">current</a>

   a bare list of historical references, prompted by what Dmitri started here, to be !include-ed into the lists of references of relevant entries, such as at cohomology, cochain cohomology, singular cohomology, cellular cohomology and probably elsewhere, too

   v1, current

2. • CommentRowNumber2.
   • CommentAuthorUrs
   • CommentTimeMay 22nd 2022
   • (edited May 22nd 2022)
   • PermaLink
   Author: Urs
   Format: MarkdownItexI have removed the line below the pointer to Kenneth Brown's 1973 article, claiming that his results were > probably known in one form or other before that. I see no evidence that this is true. On the contrary, this article is striking in how it established results that did not become widely understood until several decades later, when $\infty$-topos theory finally took off. <a href="https://ncatlab.org/nlab/revision/diff/cohomology+--+early+references/2">diff</a>, <a href="https://ncatlab.org/nlab/revision/cohomology+--+early+references/2">v2</a>, <a href="https://ncatlab.org/nlab/show/cohomology+--+early+references">current</a>

   I have removed the line below the pointer to Kenneth Brown’s 1973 article, claiming that his results were

   probably known in one form or other before that.

   I see no evidence that this is true. On the contrary, this article is striking in how it established results that did not become widely understood until several decades later, when $\infty$-topos theory finally took off.

   diff, v2, current

3. • CommentRowNumber3.
   • CommentAuthorUrs
   • CommentTimeMay 22nd 2022
   • (edited May 22nd 2022)
   • PermaLink
   Author: Urs
   Format: MarkdownItexHm, chasing through the page histories, it looks like I myself added that clause back in 2009 [here](https://ncatlab.org/nlab/revision/diff/cohomology/15). There I had it say "apparently" instead of "probably". I forget what this was referring to. If anyone knows a good reason to add such a disclaimer, then let's add it back in with some kind of evidence supporting it.

   Hm, chasing through the page histories, it looks like I myself added that clause back in 2009 here. There I had it say “apparently” instead of “probably”. I forget what this was referring to. If anyone knows a good reason to add such a disclaimer, then let’s add it back in with some kind of evidence supporting it.

4. • CommentRowNumber4.
   • CommentAuthorUrs
   • CommentTimeNov 1st 2023
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded pointer to: * [[Michael Barr]], *Cartan-Eilenberg cohomology and triples*, J. Pure Applied Algebra **112** 3 (1996) 219–238 \[<a href="https://doi.org/10.1016/0022-4049(95)00138-7">doi:10.1016/0022-4049(95)00138-7</a>, [pdf](https://www.math.mcgill.ca/barr/papers/coho.pdf), [[Barr-CECohomology.pdf:file]]\] * [[Michael Barr]], *Algebraic cohomology: the early days*, in *Galois Theory, Hopf Algebras, and Semiabelian Categories*, Fields Institute Communications **43** (2004) 1–26 \[<a href="https://doi.org/10.1090/fic/043">doi:10.1090/fic/043</a>, [pdf](https://www.math.mcgill.ca/barr/papers/algcohom.pdf), [[Barr-AlgebraicCohomology.pdf:file]]\] <a href="https://ncatlab.org/nlab/revision/diff/cohomology+--+early+references/3">diff</a>, <a href="https://ncatlab.org/nlab/revision/cohomology+--+early+references/3">v3</a>, <a href="https://ncatlab.org/nlab/show/cohomology+--+early+references">current</a>

   added pointer to:

   • Michael Barr, Cartan-Eilenberg cohomology and triples, J. Pure Applied Algebra 112 3 (1996) 219–238 [doi:10.1016/0022-4049(95)00138-7, pdf, Barr-CECohomology.pdf:file]

   • Michael Barr, Algebraic cohomology: the early days, in Galois Theory, Hopf Algebras, and Semiabelian Categories, Fields Institute Communications 43 (2004) 1–26 [doi:10.1090/fic/043, pdf, Barr-AlgebraicCohomology.pdf:file]

   diff, v3, current