From the webpage:
Musopen (www.musopen.org) is a 501(c)(3) non-profit focused on improving access and exposure to music by creating free resources and educational materials. We provide recordings, sheet music, and textbooks to the public for free, without copyright restrictions. Put simply, our mission is to set music free.
The New Grove Dictionary of Music and Musicians it’s not but losing our musical heritage did not happen over night.
Nor will winning it back.
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