Footnotes

...<kris@diku.dk>
  Universitetsparken 1, DK-2100 København Ø, Denmark.

...document
  LaTeX2e [3] users can use `\usepackage``[all]{xy}`.

...mode
  If you use the version 2 loading command `\input xypic` then the `v2` option will be loaded automatically.

...files
  The temporary files are named the same as your document but `.tex` is replaced by `-`n`.xyc` where n is a sequence number.

...bit
  `A bit' is in fact a TeX `\jot` which is usually 3pt.

...143144...145
  The plain TeX\ command corresponding to `\mbox` in LaTeX and `\text` in AMS-TeX.

...Moore,
  MPCE, Mathematics Department, Macquarie University, North Ryde, Sydney, Australia 2109; e-mail: ross@mpce.mq.edu.au.