Citazione APA

Tunkin, G. I., & Butler, W. E. (1974). Theory of International Law. Allen & Unwin.

Stile di citazione Chicago

Tunkin, G I., e William E. Butler. Theory of International Law. London: Allen & Unwin, 1974.

Citazione MLA

Tunkin, G I., e William E. Butler. Theory of International Law. Allen & Unwin, 1974.