"Public international law governs the relationships between national governments and intergovernmental organizations. It regulates governments and intergovernmental organizations across national boundaries." Marci Hoffman and Katherine Topolos, International Legal Research Tutoria: Public International Lawl (last visited Jan. 23, 2013).
Video link (40 minutes)
Source: United Nations Audio Visual Library, The Sources of International Law
Judge Christopher Greenwood, International Court of Justice
Codification Division, Office of Legal Affairs
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a. International Conventions, whether general or particular, establishing rules expressly recognized by the contesting states;
b. International Custom, as evidence of a general practice accepted as law;
c. the General Principles of Law recognized by civilized nations;
d. subject to the provisions of Article 59, Judicial Decisions and the Teachings of the Most Highly Qualified Publicists of the various nations, as subsidiary means for the determination of rules of law.
Article 38, ¶ 1. of the Statute of the International Court of Justices
From the Restatement (Third) of Foreign Relations Law § 102 (1987)
(1) A rule of international law is one that has been accepted as such by the international community of states
Rüdiger Wolfrum, Sources of International Law, Max Planck Encyclopedia of Public International Law (last updated May 2011)
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