Graph-Graph6 is Copyright 2015, 2016, 2017, 2018 Kevin Ryde

Graph-Graph6 is licensed under the GNU General Public License GPL
version 3 (or at your option any later version).  The complete text of
GPL version 3 is in the file

    /usr/share/common-licenses/GPL-3

Program home page:

    http://user42.tuxfamily.org/graph-graph6/index.html