/usr/local/share/groff/1.23.0/tmac/m.tmac
is the groff implementation of the memorandum macros.
/usr/local/share/groff/1.23.0/tmac/mm.tmac
is wrapper to load m.tmac.
/usr/local/share/groff/1.23.0/tmac/mm/ms.cov
implements an ms-like cover sheet.
/usr/local/share/groff/1.23.0/tmac/mm/0.MT
implements memorandum types 0–3 and 6.
/usr/local/share/groff/1.23.0/tmac/mm/4.MT
implements memorandum type 4.
/usr/local/share/groff/1.23.0/tmac/mm/5.MT
implements memorandum type 5.
/usr/local/share/groff/1.23.0/tmac/mm/locale
performs any (further) desired necessary localization;
empty by default.