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• CommentRowNumber1.
• CommentAuthorronniegpd
• CommentTimeSep 30th 2012
I have added some information on the work of Henry Whitehead which is related to this topic, and referred to work of Graham Ellis, and of Higgins and I, which is relevant.

I expect I have not given the best code for all of this so someone may want to improve it in that respect.

Graham, also writes in his paper:

In view of the ease with which Whitehead's methods handle the
classifications of Olum and Jajodia, it is surprising that the
papers \cite{olum:1953} and \cite{jaj:1980} (both of which were
written after the publication of \cite{whjhc:1949}) make
respectively no use, and so little use, of \cite{whjhc:1949}.

We note here that B. Schellenberg, who was a student of Olum, has
rediscovered in \cite{sch:1973} the main classification theorems
of \cite{whjhc:1949}. The paper \cite{sch:1973} relies heavily on
earlier work of Olum.
• CommentRowNumber2.
• CommentAuthorTodd_Trimble
• CommentTimeSep 30th 2012

I had trouble detecting the article you added to, before I finally resorted to “Recently Revised”: history of cohomology with local coefficients

• CommentRowNumber3.
• CommentAuthorTim_Porter
• CommentTimeOct 1st 2012

At present there seems to be discussion of non-abelian $H^2$ but almost nothing on $H^1$, with or without local coefficients. (I point this out as I am trying to write a section in the monograph I am working on, that makes the link between Serre’s definition of non-abelian $H^1(G,A)$ and the corresponding $H^1$ for simplicial profinite spaces. … and the task is proving difficult at the level I am assuming for the reader!

• CommentRowNumber4.
• CommentAuthorronniegpd
• CommentTimeOct 1st 2012
Tim: I wonder if the notions of "fibrations of groupoids" and "groupoids as coefficients" are relevant: I would like to believe they were! (10 and 11 on my pub list, and downloadable). They both deal with nonabelian cohomology.