Cita APA (7a ed.)
Roberts, J., & Curtis, H. (1973). Civilization: Volume 1: the emergence of man in society. Communications research machines.
Cita Chicago Style (17a ed.)
Roberts, John, y Helena Curtis. Civilization: Volume 1: The Emergence of Man in Society. California: Communications research machines, 1973.
Cita MLA (9a ed.)
Roberts, John, y Helena Curtis. Civilization: Volume 1: The Emergence of Man in Society. Communications research machines, 1973.
Precaución: Estas citas no son 100% exactas.