Cita APA (7a ed.)

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

Cita Chicago Style (17a ed.)

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

Cita MLA (8a ed.)

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