APA (7th ed.) Citation

Educators' Progress Service, Randolph, Wis, Horkheimer, M., & Diffor, J. W. Educators' guide to free films. Educators' Progress Service.

Chicago Style (17th ed.) Citation

Educators' Progress Service, Randolph, Wis, Mary Horkheimer, and John Warren Diffor. Educators' Guide to Free Films. Randolph, Wis: Educators' Progress Service.

MLA (9th ed.) Citation

Educators' Progress Service, Randolph, Wis, et al. Educators' Guide to Free Films. Educators' Progress Service.