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• CommentRowNumber1.
• CommentAuthorMike Shulman
• CommentTimeMar 10th 2010
• (edited Mar 10th 2010)

Added some remarks, mostly about extensivity and exactness, to quasitopos.

• CommentRowNumber2.
• CommentAuthorUrs
• CommentTimeOct 20th 2010

added a bunch of propositions to quasitopos

• CommentRowNumber3.
• CommentAuthorUrs
• CommentTimeOct 26th 2010

added references to quasitopos and concrete sheaf

• CommentRowNumber4.
• CommentAuthorUrs
• CommentTimeDec 8th 2011

added a pointer to Garner and Lack which appeared earlier this year.

• CommentRowNumber5.
• CommentAuthorTodd_Trimble
• CommentTimeOct 3rd 2013

Some slight rearrangement of examples, recognizing five of them as examples of $\neg\neg$-separated presheaves. See this MSE thread.

• CommentRowNumber6.
• CommentAuthorMike Shulman
• CommentTimeMar 1st 2018

We discovered on MO that the page quasitopos has contained an incorrect definition of “Grothendieck quasitopos” for the past 8 years, which was apparently my fault originally. Ugh. Now fixed.

• CommentRowNumber7.
• CommentAuthorTodd_Trimble
• CommentTimeMar 1st 2018

I added a second characterization for Grothendieck quasitopos.

• CommentRowNumber8.
• CommentAuthorpcapriotti
• CommentTimeSep 25th 2018

Added a little bit more information to the remark about the alternative definition of quasitopos, and a reference to Wyler for the trickiest step in the proof.

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