CREDITS.SID

 CREDITS According to Alvaro Lopes <alvieboy@alvie.com>
 
 Credits for SID implementation go to Jan Derogee, who did the VHDL implementation,
 and to Robert Yannes, who did the original SID chip.
 
 License for the VHDL code, unless otherwise stated is (according to an email from Jan):
 
	"everyone may use it, when changes are made make them public 
         for the benefit of all, keeping it open source" 


https://en.wikipedia.org/wiki/Robert_Yannes

Alvaro is also the author of the SID filter module, which he has released under the BSD license:

-- (C) Alvaro Lopes <alvieboy@alvie.com>
-- 
--   The FreeBSD license
-- 
--   Redistribution and use in source and binary forms, with or without
--   modification, are permitted provided that the following conditions
--   are met:
-- 
--   1. Redistributions of source code must retain the above copyright
--      notice, this list of conditions and the following disclaimer.
--   2. Redistributions in binary form must reproduce the above
--      copyright notice, this list of conditions and the following
--      disclaimer in the documentation and/or other materials
--      provided with the distribution.
-- 
--   THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY
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--   ZPUINO PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
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--   (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
--   OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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