Cita APA (7a ed.)

Wittich, W. A., & Schuller, C. F. (1957). Audio-visual materials: Their nature and use (2nd ed.). Harper & Brothers.

Cita Chicago Style (17a ed.)

Wittich, Walter Arno, y Charles Francis Schuller. Audio-visual Materials: Their Nature and Use. 2nd ed. New York: Harper & Brothers, 1957.

Cita MLA (9a ed.)

Wittich, Walter Arno, y Charles Francis Schuller. Audio-visual Materials: Their Nature and Use. 2nd ed. Harper & Brothers, 1957.