Cita APA (7th ed.)

Wittich, W. A., & Schuller, C. F. (1967). Audio-visual materials; their nature and use (4th ed.). Harper & Row.

Cita Chicago (17th ed.)

Wittich, Walter A., i Charles Francis Schuller. Audio-visual Materials; Their Nature and Use. 4th ed. New York: Harper & Row, 1967.

Cita MLA (8th ed.)

Wittich, Walter A., i Charles Francis Schuller. Audio-visual Materials; Their Nature and Use. 4th ed. Harper & Row, 1967.