Williams, S. (1987). An Introduction to International law (2nd.ed.). Butterworths.
Dyfyniad Arddull ChicagoWilliams, S.A. An Introduction to International Law. 2nd.ed. Toronto: Butterworths, 1987.
Dyfyniad MLAWilliams, S.A. An Introduction to International Law. 2nd.ed. Butterworths, 1987.
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