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3. Adorno, Theodor W. In Search of Wagner. Trans. Rodney Livingstone. London: Verso, 1991.
4. Aldritch, Richard. A Guide to The Ring of the Nibelung. Boston: Oliver Ditson, 1905.
5. Boretz, Benjamin. “Nelson Goodman’s Languages of Art from a Musical Point of View.” Perspectives on Contemporary Music Theory. Ed. Benjamin Boretz and Edward T. Cone. New York: W. W. Norton, 1972. 31–44.