Double groupoids and crossed modules

Double groupoids and crossed modules

[Ronnie Brown]

Hi,

In clearing out my office at Bangor University (which for two years or
more I have hardly used) I came across the  first version of my work
with Chris Spencer;   this  was rejected by Saunders for JPAA, after two
negative reports (one described it as "good file drawer stuff",  and the
other remarked that part was known to Verdier and not published. So it
was eventually revised into 2 papers, and published elsewhere, in 1976.
I decided to scan it to have it on my files, and in case anyone else was
interested. It contains some accounts of homotopies and  a Whitehead
theorem, not published elsewhere, except as part of work in the mid
1980s with Philip Higgins. So this is now available,  as they say "as
is", on my preprint page,

http://pages.bangor.ac.uk/~mas010/brownpr.html
<http://pages.bangor.ac.uk/%7Emas010/brownpr.html>

which also has a recent  presentation on John Robinson, sculptor.

Ronnie

-- 
my web page:

http://www.bangor.ac.uk/r.brown

Our Snowdonia Holiday cottage:

http://www.tremyfoel.co.uk



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