Copyright

All files, unless stated otherwise, are 
(C) 1999-2018
    Gertjan van Noord, Gosse Bouma, Rob Malouf,
    Robbert Prins, Begona Villada, Jan Daciuk,
    Tanja Gaustad, Leonoor van der Beek, Geert Kloosterman, 
    Daniel de Kok, NWO/RUG. 

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the 
    Free Software Foundation, Inc., 
    51 Franklin Street, Fifth Floor, Boston, 
    MA  02110-1301  USA

cf. the file COPYING