Cita APA (7a ed.)

Walker, N. (1991). Why punish? Oxford Univ. Press.

Cita Chicago Style (17a ed.)

Walker, Nigel. Why Punish? Oxford [u.a.]: Oxford Univ. Press, 1991.

Cita MLA (9a ed.)

Walker, Nigel. Why Punish? Oxford Univ. Press, 1991.