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Music History of the Western World
Coursera
Coursera course: 20世纪西方音乐 Western Music in the 20th Century
More resources on Music History
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allmusic.com
AllMusic is a comprehensive music database offering artist biographies, discographies, album reviews, and genre/history context, along with editorials and detailed credits for albums and tracks.
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khanacademy.org
Khan Academy offers free, self-paced lessons across many subjects, including Music History. It features video lessons, readings, listening analyses, and practice questions on composers, periods, and key works.
WebsiteFree
berklee.edu
Official site of Berklee College of Music, offering information on degree programs, admissions, news and events, and access to music education resources and courses, including material relevant to music history.