APA (7th ed.) Citation

Watkins, P. (1967). The war game: World War Three, this is how it may begin. Avon Books.

Chicago Style (17th ed.) Citation

Watkins, Peter. The War Game: World War Three, This Is How It May Begin. New York, N.Y: Avon Books, 1967.

MLA (9th ed.) Citation

Watkins, Peter. The War Game: World War Three, This Is How It May Begin. Avon Books, 1967.