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Customary International Law: Introduction

Definitions of Customary International Law

Custom as a Source of Law

Interpreting Customary International Law

"...it is vitally important to say that unwritten law...is law. This includes Customary International Law, whatever mistaken publicists may teach, even publicists of the most highly qualified kind, and whatever hypocritical and self-serving governments and their sycophantic intellectual camp-followers may say. There is little enough public order in the intergovernmental world without despising the modicum of intelligent self-ordering that, over long centuries, it has been able to find within itself." (Philip Allott, Interpretation in International Law, 386)