APA Citation

Roberts, H. C. M. a. A. B. (1949). Audio-visual aids to instruction. European university studies.

Chicago Style Citation

Roberts, Harry C. McKowin and Alvin B. Audio-visual Aids to Instruction. European university studies, 1949.

MLA Citation

Roberts, Harry C. McKowin and Alvin B. Audio-visual Aids to Instruction. European university studies, 1949.

Warning: These citations may not always be 100% accurate.