Burns, E. M., & Ralph, P. L. (1982). World civilizations: Their history and their culture (6. ed.). Norton.
Citazione stile Chigago Style (17a edizione)Burns, Edward McNall, e Philip Lee Ralph. World Civilizations: Their History and Their Culture. 6. ed. New York: Norton, 1982.
Citatione MLA (9a ed.)Burns, Edward McNall, e Philip Lee Ralph. World Civilizations: Their History and Their Culture. 6. ed. Norton, 1982.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.