Cita APA (7a ed.)

Zimmern, A. (1931). The study of international relations. The Clarendon Press.

Cita Chicago Style (17a ed.)

Zimmern, Alfred. The Study of International Relations. Oxford: The Clarendon Press, 1931.

Cita MLA (9a ed.)

Zimmern, Alfred. The Study of International Relations. The Clarendon Press, 1931.