Citazione Stile APA (7a Edizione)

National geographic society, Boehm, R. G., & Bednarz, S. W. (1999). World geography: A physical and cultural approach. Glencoe, McGraw-Hill.

Citazione stile Chigago Style (17a edizione)

National geographic society, Richard G. Boehm, e Sarah W. Bednarz. World Geography: A Physical and Cultural Approach. New York, NY [u.a.]: Glencoe, McGraw-Hill, 1999.

Citatione MLA (9a ed.)

National geographic society, et al. World Geography: A Physical and Cultural Approach. Glencoe, McGraw-Hill, 1999.