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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeApr 8th 2011
   • (edited Apr 8th 2011)
   • PermaLink
   Author: Urs
   Format: MarkdownItexBas Spitters has kindly pointed out to me that the proof by Banaschewski and Mulvey of Gelfand duality is not actually constructive, as it invokes [[Barr's theorem]], and that he has a genuine constructive and also simpler proof with Coquand. I have added that to the refrences at [[constructive Gelfand duality theorem]]

   Bas Spitters has kindly pointed out to me that the proof by Banaschewski and Mulvey of Gelfand duality is not actually constructive, as it invokes Barr’s theorem, and that he has a genuine constructive and also simpler proof with Coquand. I have added that to the refrences at constructive Gelfand duality theorem