APA (7th ed.) Citation

Koningsberger, H. (1961). An American romance. Penguin Books.

Chicago Style (17th ed.) Citation

Koningsberger, Hans. An American Romance. Harmondsworth, Middlesex, Eng: Penguin Books, 1961.

MLA (9th ed.) Citation

Koningsberger, Hans. An American Romance. Penguin Books, 1961.