Rectanus, Hans. “Wechsel der Unterrichtsformen unter Einbeziehung verschiedener Medien als didaktische Notwendigkeit im Musikunterricht,” 101-111. In Medieninvasion: die Kulturpolitische Verantwortung der Musikerziehung. Mainz, Germany: Schott, 1985.

Rathert, Wolfgang. “The idea of potentiality in the music of Charles Ives.” In Ives Studies, edited by Philip Lambert, 105-132. Cambridge, United Kingdom: Cambridge University Press, 1997.

Rahmanova, Marina. “Charles Ives.” Sovetskaja muzyka 6 (June 1971): 97-108.

Putz, Werner, Peter Virnich, and Peter Winz-Luckei. “Neue Musik handelnd erfahren: Eine Unterrichtsreihe zu Charles Ives und John Cage.” Musik und Bildung 19/5 (1987): 350-358.

Porter, Ellen Jane Lorenz. “A Treasure of Camp-Meeting Spirituals.” Ph.D. diss., Union Graduate School, Cincinnati, Ohio, 1978.

Perlis, Vivian. “‘Monumenta Americana’ Revisited.” In A Celebration of American Music: Words and Music in Honor of H. Wiley Hitchcock, 439-448. Edited by Richard Crawford, R. Allen Lott, and Carol J. Oja. Ann Arbor: Univer-sity of Michigan Press, 1990.

Perkins. Francis D. “Letters: In Defense of Critics.” Harper’s 197 (Decem-ber 1948): 14.

Pearsall, Ronald. “Ives in Performance.” Music Review 47/1 (1986-87): 24-28.

Orrey, Leslie. Programme Music: A Brief Survey from the Sixteenth Century to the Present Day. London, United Kingdom: Davis-Poynter, 1975.

O'Reilly, F. Warren. “Charles Ives: American Patriot, Prophetic Genius, Mod-ern Non-Conformist.” In South Florida's Historic Ives Festival, 1974-1976, 47-49. Coral Gables, FL: University of Miami, 1976.