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International Law: General Sources: Sources for researching state practice of international law

This guide lists essential sources for researching general aspects of international law. For specialized topics, such as human rights and international arbitration, see the guide International Law: Specialized Sources.

What types of actions and documents show state practice and opinio juris?

Various research guides, books and articles provide lists of the types of state actions and documents that might be evidence of "state practice" and/or opinio juris. See Research strategies & selected books, e.g., Kuehl & O'Brien, International Legal Research in a Global Community, at 76.

Use the other tabs of this research guide to locate any specific sources that you need, e.g., U.S. practice of international law, treaties, case law/jurisprudence, international organizations, etc.

General sources, including information on state practice by other states