Copyright for approx source package in Xenial

approx: proxy server for Debian archive files
Copyright (C) 2011  Eric C. Cooper 
Homepage: http://git.debian.org/?p=pkg-ocaml-maint/packages/approx.git

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 of the License, 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, write to the Free Software Foundation, Inc.,
51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

On Debian GNU/Linux systems, the complete text of version 2 of the
GNU General Public License can be found in /usr/share/common-licenses/GPL-2.