Dreyfus, K. (1971). Beethoven's last five piano sonatas: A study in analytical method.
Lua i Stíl Chicago (17ú heag.)Dreyfus, Kay. Beethoven's Last Five Piano Sonatas: A Study in Analytical Method. 1971.
Lua MLA (8ú heag.)Dreyfus, Kay. Beethoven's Last Five Piano Sonatas: A Study in Analytical Method. 1971.
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