Twentieth Century: The History of the World, 1901 to 2000

MLA

Roberts, J. M. Twentieth Century: The History of the World, 1901 to 2000. Harmondsworth: Viking, 1999.

APA

Roberts, J. M. (1999). Twentieth Century: The History of the World, 1901 to 2000. Harmondsworth: Viking.

Chicago

Roberts, J. M. Twentieth Century: The History of the World, 1901 to 2000. Harmondsworth: Viking, 1999.