Citazione Stile APA (7a Edizione)

Whitbeck, R. H., Williams, F. E., & Christians, W. F. (1940). Economic geography of South America. McGraw-Hill.

Citazione stile Chigago Style (17a edizione)

Whitbeck, Ray Hughes, Frank Ernest Williams, e William Florian Christians. Economic Geography of South America. New York: McGraw-Hill, 1940.

Citatione MLA (9a ed.)

Whitbeck, Ray Hughes, et al. Economic Geography of South America. McGraw-Hill, 1940.