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1. • CommentRowNumber1.
   • CommentAuthorTim_Porter
   • CommentTimeSep 3rd 2010
   • (edited Sep 3rd 2010)
   • PermaLink
   Author: Tim_Porter
   Format: MarkdownItexI have added a bit of history to the entry on [[Baues-Wirsching cohomology]]. Whilst looking for something else I found a paper by Charlie Wells from 1979, extending the earlier ideas of Leech cohomology for semigroups to small categories. He defines various types of extension and classifies them using the same methods as B and W used a few years later.

   I have added a bit of history to the entry on Baues-Wirsching cohomology. Whilst looking for something else I found a paper by Charlie Wells from 1979, extending the earlier ideas of Leech cohomology for semigroups to small categories. He defines various types of extension and classifies them using the same methods as B and W used a few years later.