APA (7th ed.) Citation

Helmer, W., & Mattix, R. (1998). Public enemies: America's criminal past, 1919 - 1940. Checkmark Books.

Chicago Style (17th ed.) Citation

Helmer, William, and Rick Mattix. Public Enemies: America's Criminal Past, 1919 - 1940. New York, NY: Checkmark Books, 1998.

MLA (9th ed.) Citation

Helmer, William, and Rick Mattix. Public Enemies: America's Criminal Past, 1919 - 1940. Checkmark Books, 1998.