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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeSep 4th 2010

    added a list of examples to Lie groupoid

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeSep 4th 2010

    I saw some loose ends and made some half-hearted attempts to start filling them without really having time for this. But I created stubs for

    and

    • CommentRowNumber3.
    • CommentAuthorJohn Baez
    • CommentTimeJul 24th 2011

    In Lie groupoid I changed

    One way to deal with this is to equip the 2-category with some structure of a homotopical category and allow morphisms of Lie groupoids to be 2-anafunctors, i.e. spans of internal functors XˆXY.

    to

    One way to deal with this is to equip the 2-category with some structure of a homotopical category and allow morphisms of Lie groupoids to be anafunctors, i.e. spans of internal functors XˆXY.

    If it’s wrong, change it back and let me know the error of my ways!

    (I’m writing a little paper with Derek Wise on gravity and higher gauge theory, and I was looking for standard references on Lie groupoids…)

    • CommentRowNumber4.
    • CommentAuthorTobyBartels
    • CommentTimeJul 24th 2011

    You’re correct!

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeMay 20th 2019

    I was looking for any online incarnation of

    • Charles Ehresmann, Catégories topologiques et catégories différentiables, Colloque de Géometrie Differentielle Globale (Bruxelles, 1958), 137–150, Centre Belge Rech. Math., Louvain, 1959;

    such as a doi, or a jstor entry. Anything?

    diff, v62, current

    • CommentRowNumber6.
    • CommentAuthorTim_Porter
    • CommentTimeMay 20th 2019

    Try page 263 of http://ehres.pagesperso-orange.fr/C.E.WORKS_fichiers/Ehresmann_C.-Oeuvres_I-1_et_I-2.pdf, i.e. Ehresmann’s collected works. I think that is what you need.

    • CommentRowNumber7.
    • CommentAuthorUrs
    • CommentTimeMay 20th 2019

    Thanks. Might you know which page in that big file corresponds to the above article?

    (It doesn’t seem to be searchable…)

    • CommentRowNumber8.
    • CommentAuthorDavidRoberts
    • CommentTimeMay 20th 2019

    I’ll send you a copy of the paper itself, Urs.

    • CommentRowNumber9.
    • CommentAuthorUrs
    • CommentTimeMay 20th 2019

    Thanks, but I don’t need to read the paper myself, instead I want to cite it in a way that is useful to others. May we upload it here?

    • CommentRowNumber10.
    • CommentAuthorTim_Porter
    • CommentTimeMay 20th 2019
    • (edited May 20th 2019)

    Why not give the link and then add ’starting on page 263’?

    Is there a link to the collected works somewhere on the Lab? If not it may be worth while adding.

    • CommentRowNumber11.
    • CommentAuthorUrs
    • CommentTimeMay 20th 2019

    Hi Tim, ah, thanks for saying that again, had missed that. Okay, am adding the pointer to this now.

    (If this is online, I guess David’s more tractable copy may be put online, too. But it has a scary all-capital copyright WARNING right at the beginning, which intimidates even me… )

    • CommentRowNumber12.
    • CommentAuthorDavidRoberts
    • CommentTimeMay 20th 2019
    • (edited May 20th 2019)

    Yeah, please don’t upload my copy. I did get it under careful arrangements before the whole lot was scanned and put online. I think pointing to the official copy should be sufficient for now. My only worry was that the scanning had gone wrong (like on a few other pages) but I checked and it’s ok.

    • CommentRowNumber13.
    • CommentAuthorUrs
    • CommentTimeMay 20th 2019

    Sure. Okay, thanks.

    • CommentRowNumber14.
    • CommentAuthorUrs
    • CommentTimeJul 27th 2021

    have removed dead links and instead added working DOI-links for these Reference-items:

    diff, v66, current