Copyright for r-cran-truncdist source package in Focal

Format: https://www.debian.org/doc/packaging-manuals/copyright-format/1.0/
Upstream-Name: truncdist
Upstream-Contact: Frederick Novomestky 
Source: https://cran.r-project.org/package=truncdist

Files: *
Copyright: 2016 Frederick Novomestky 
           2016 Saralees Nadarajah 
License: GPL-2+

Files: debian/*
Copyright: 2018 Sébastien Villemot 
License: GPL-2+

License: GPL-2+
 This program is free software; you can redistribute it and/or
 modify it under the terms of the GNU General Public License as
 published by the Free Software Foundation; either version 2,
 or (at your option) any later version.
 .
 This program 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 General Public License for more details.
 .
 You should have received a copy of the GNU General Public License along
 with this program. If not, see .
 .
 On Debian systems, the complete text of the GNU General Public
 License, version 2, can be found in the file
 `/usr/share/common-licenses/GPL-2'.