APA (7e ed.) Bronvermelding

Beckman, P. R. (1984). World politics in the twentieth century. Prentice-Hall.

Chicago (17e ed.) Bronvermelding

Beckman, Peter R. World Politics in the Twentieth Century. Englewood Cliffs, New Jersey: Prentice-Hall, 1984.

MLA (9e ed.) Bronvermelding

Beckman, Peter R. World Politics in the Twentieth Century. Prentice-Hall, 1984.