For reference: The only place I've been able to find the PDF of Ted
Harding's “A Guide to Typesetting Mathematics using GNU eqn” (the link
from troff.org is broken) is in the archives of the groff mailing
list and archive.org (search for “eqnguide”, since the file is named
The last was the most recent I found, labeled “Last Revised 27 October 2013”. It is also available from archive.org.
Does anyone know of the source to this was ever released?