Cita APA (7a ed.)

Williams, C. A. (2011). Police and policing in the twentieth century. Ashgate.

Cita Chicago Style (17a ed.)

Williams, Chris A. Police and Policing in the Twentieth Century. Farnham [u.a.]: Ashgate, 2011.

Cita MLA (8a ed.)

Williams, Chris A. Police and Policing in the Twentieth Century. Ashgate, 2011.