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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeAug 24th 2012

    statement of the 3x3 lemma

    • CommentRowNumber2.
    • CommentAuthorMike Shulman
    • CommentTimeAug 24th 2012

    There’s also a 3x3 lemma for triangulated categories.

    • CommentRowNumber3.
    • CommentAuthorKeith Harbaugh
    • CommentTimeAug 2nd 2019

    Added link to Bourn’s 2003 paper “The denormalized 3×33\times3 lemma”, which extended the lemma, for rows and columns of (kernel relation/coequalizer) pairs, to many suitable UNPOINTED categories.

    diff, v12, current

    • CommentRowNumber4.
    • CommentAuthorKeith Harbaugh
    • CommentTimeAug 2nd 2019

    HELP! Embedded () pair within the doi of the last reference (and the most recent edit) conflicts with usage of () to denote the link. I have no idea of how to fix this problem.

    diff, v12, current

    • CommentRowNumber5.
    • CommentAuthorRichard Williamson
    • CommentTimeAug 2nd 2019
    • (edited Aug 2nd 2019)

    I’d suggest to use the HTML encoding of the brackets inside the link. They can be found here.

    • CommentRowNumber6.
    • CommentAuthorKeith Harbaugh
    • CommentTimeAug 2nd 2019

    Inserted HTML character codes for () within doi. Hope that fixes the problem. Thanks Robert Williamson!

    diff, v13, current

  1. My apologies, got my wires crossed, it is URL encoding that is needed in this case, I have fixed it now.

    • CommentRowNumber8.
    • CommentAuthorDavidRoberts
    • CommentTimeAug 4th 2019

    Moved doi link to (Bourn 2003) to it’s own anchor, spelling out the doi, rather than having it attached to the name of the paper, with the break in the link due to the MathJax rendering

    diff, v15, current