APA

(1977). Great Events of the 20th century. London: The Reader's Digest Association.

Chicago

1977. Great Events of the 20th century. London: The Reader's Digest Association.

Harvard

(1977). Great Events of the 20th century. London: The Reader's Digest Association.

MLA

Great Events of the 20th century. London: The Reader's Digest Association. 1977.