Cita APA (7a ed.)

Walker, S. (1983). The police in America: An introd. McGraw-Hill.

Cita Chicago Style (17a ed.)

Walker, Samuel. The Police in America: An Introd. New York [u.a.]: McGraw-Hill, 1983.

Cita MLA (8a ed.)

Walker, Samuel. The Police in America: An Introd. McGraw-Hill, 1983.