See full history on Github to check all authors.
COPS use some external librairies, check README for the details.
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License version 2 as published by the Free Software Foundation.
The complete content of license is provided in file COPYING within distribution and also available online.
For more info please visit COPS Home Page
You can also check COPS's topic on MobileRead forum.