APA (7th ed.) Citation

Knightley, P. (1988). The second oldest profession: Spies and spying in the twentieth century. Penguin.

Chicago Style (17th ed.) Citation

Knightley, Phillip. The Second Oldest Profession: Spies and Spying in the Twentieth Century. New York: Penguin, 1988.

MLA (9th ed.) Citation

Knightley, Phillip. The Second Oldest Profession: Spies and Spying in the Twentieth Century. Penguin, 1988.