mandoc.css is included in OpenGrok under the following license:

$Id: LICENSE,v 1.17 2017/06/23 15:58:14 schwarze Exp $

With the exceptions noted below, all code and documentation
contained in the mandoc toolkit is protected by the Copyright
of the following developers:

Copyright (c) 2008-2012, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
Copyright (c) 2010-2017 Ingo Schwarze <schwarze@openbsd.org>
Copyright (c) 2009, 2010, 2011, 2012 Joerg Sonnenberger <joerg@netbsd.org>
Copyright (c) 2013 Franco Fichtner <franco@lastsummer.de>
Copyright (c) 2014 Baptiste Daroussin <bapt@freebsd.org>
Copyright (c) 2016 Ed Maste <emaste@freebsd.org>
Copyright (c) 2017 Michael Stapelberg <stapelberg@debian.org>
Copyright (c) 1999, 2004 Marc Espie <espie@openbsd.org>
Copyright (c) 1998, 2004, 2010 Todd C. Miller <Todd.Miller@courtesan.com>
Copyright (c) 2008, 2017 Otto Moerbeek <otto@drijf.net>
Copyright (c) 2004 Ted Unangst <tedu@openbsd.org>
Copyright (c) 1994 Christos Zoulas <christos@netbsd.org>
Copyright (c) 2003, 2007, 2008, 2014 Jason McIntyre <jmc@openbsd.org>

See the individual source files for information about who contributed
to which file during which years.


The mandoc distribution as a whole is distributed by its developers
under the following license:

Permission to use, copy, modify, and distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.


The following files included from outside sources are protected by
other people's Copyright and are distributed under various 2-clause
and 3-clause BSD licenses; see these individual files for details.

soelim.c, soelim.1:
Copyright (c) 2014 Baptiste Daroussin <bapt@freebsd.org>

compat_err.c, compat_fts.c, compat_fts.h,
compat_getsubopt.c, compat_strcasestr.c, compat_strsep.c,
man.1:
Copyright (c) 1989,1990,1993,1994 The Regents of the University of California

compat_stringlist.c, compat_stringlist.h:
Copyright (c) 1994 Christos Zoulas <christos@netbsd.org>
