References

GNU

http://www.gnu.org

The GNU Hurd

http://hurd.gnu.org

Debian GNU/Hurd

http://www.debian.org/ports/hurd

HurdFr

http://hurdfr.org or #hurdfr on irc.freenode.net

L4

http://www.l4ka.org

The GNU manifesto

http://www.gnu.org/gnu/manifesto.html