APA (7th ed.) Citation

Downs, R. B. (1939). Guide for the description and evaluation of research materials. American Library Association.

Chicago Style (17th ed.) Citation

Downs, Robert B. Guide for the Description and Evaluation of Research Materials. Chicago: American Library Association, 1939.

MLA (9th ed.) Citation

Downs, Robert B. Guide for the Description and Evaluation of Research Materials. American Library Association, 1939.