Citazione Stile APA (7a Edizione)

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

Citazione stile Chigago Style (17a edizione)

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

Citatione MLA (9a ed.)

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