LICENSE.txt

License of media (textures and sounds)
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Copyright (C) 2010-2012 celeron55, Perttu Ahola <celeron55@gmail.com>
See README.txt in each mod directory for information about other authors.

Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0)
http://creativecommons.org/licenses/by-sa/3.0/

License of menu/header.png
Copyright (C) 2015 paramat CC BY-SA 3.0


License of source code
----------------------
Copyright (C) 2010-2012 celeron55, Perttu Ahola <celeron55@gmail.com>
See README.txt in each mod directory for information about other authors.

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That's all there is to it!