Just a Tip When Searching for Sources...
Primary sources might include letters (also called correspondance), interviews, memoirs or autbiographies, and documentary films. The correspondance and personal papers of well-known people is often published in book form, so it is possible that they'd be in the library. Try adding a term like "interviews" or "correspondance" when you're using a composer's name to search, or just be on the lookout for these types of materials in your search results.
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