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http://www.bensound.com/licensing
https://licensing.jamendo.com/de/katalog/suche
http://creativecommons.org
http://www.makeuseof.com/tag/14-websites-to-find-free-creative-commons-music
ZHDK Sound Library Access (local and VPN)
https://library.prosoundeffects.com/
Concept Video examples
https://vimeo.com/43038579
http://vimeo.com/72421005
http://vimeo.com/15817751
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