ftp://ftp.sk.freebsd.org/pub/NetBSD/NetBSD-release-3-0/src/gnu/dist/groff/src/roff/  direct

[DIR]CVS/  direct  1000+ twin directories
[DIR]groff/  direct  1000+ twin directories
[DIR]grog/  direct  400+ twin directories
[DIR]nroff/  direct  420+ twin directories
[DIR]troff/  direct  480+ twin directories