Cita APA (7th ed.)

Gaddum, L. W., & Knowles, H. L. (1953). Our physical environment: A problem approach. University of Florida.

Cita Chicago (17th ed.)

Gaddum, Leonard W., i Harold L. Knowles. Our Physical Environment: A Problem Approach. Boston, Mass.: University of Florida, 1953.

Cita MLA (9th ed.)

Gaddum, Leonard W., i Harold L. Knowles. Our Physical Environment: A Problem Approach. University of Florida, 1953.