Amazon note:  Source for 7-zip is hosted at 
https://s3-us-west-2.amazonaws.com/ly-legal/LicenseConformance/7-zip/18.05/7z1805-src.7z



      7-Zip Extra
      ~~~~~~~~~~~
      License for use and distribution
      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

      Copyright (C) 1999-2015 Igor Pavlov.

      7-Zip Extra files are under the GNU LGPL license.

      
      Notes: 
        You can use 7-Zip Extra on any computer, including a computer in a commercial 
        organization. You don't need to register or pay for 7-Zip.


      GNU LGPL information
      --------------------

        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 can receive a copy of the GNU Lesser General Public License from 
        http://www.gnu.org/