Roberts, J. M. (1980). The Pelican history of the world. Harmondsworth: Penguin Books.
Chicago Style aipamenaRoberts, J. M. The Pelican History of the World. Harmondsworth: Penguin Books, 1980.
MLA aipamenaRoberts, J. M. The Pelican History of the World. Harmondsworth: Penguin Books, 1980.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.