The source code to this library used with SDL_mixer can be found here:
https://hg.libsdl.org/SDL_mixer/file/default/external
---

Copyright 2001-2011 Xiph.Org, Skype Limited, Octasic,
                    Jean-Marc Valin, Timothy B. Terriberry,
                    CSIRO, Gregory Maxwell, Mark Borgerding,
                    Erik de Castro Lopo

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