Some of these documents use a font called CW.
If this font is not available, reference to it can be changed with
a sed-script like
	s/\.ft CW/.ft yourfont/
	s/\\f(CW/\\fyourfont/g
	s/^.fp\(.*\)CW$/.fp\1yourfont/
However, the font must be a constant-width font for the documents to look
reasonable.