Cita APA (7a ed.)

Burns, E. M., & Ralph, P. L. (1969). World civilizations: Their history and their culture (4. ed.). Norton.

Cita Chicago Style (17a ed.)

Burns, Edward McNall, y Philip Lee Ralph. World Civilizations: Their History and Their Culture. 4. ed. New York: Norton, 1969.

Cita MLA (9a ed.)

Burns, Edward McNall, y Philip Lee Ralph. World Civilizations: Their History and Their Culture. 4. ed. Norton, 1969.