4.4BSD snapshot (revision 8.1); add 1993 to copyright
macro and text revision (-mdoc version 3)
intro(3M) => math(3M), move see also's to end
new from Kahan
Revision by Prof. Kahan.
Expand the Notes section.
From Prof. Kahan
4.3BSD beta release manual page
manual page distributed with 4.2BSD
manual page distributed with 4.1BSD