Cita APA (7a ed.)

Keylor, W. R. (1984). The Twentieth-Century World. Oxford University Press.

Cita Chicago Style (17a ed.)

Keylor, William R. The Twentieth-Century World. New York ; Oxford: Oxford University Press, 1984.

Cita MLA (9a ed.)

Keylor, William R. The Twentieth-Century World. Oxford University Press, 1984.