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International Law: General Sources: Research strategies & selected books

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.

How to start research in customary international law

The research guides and books on this page introduce the concepts of customary international law, state practice, opinio juris, and jus cogens. Some of them, in particular, Winer, Kuehl & O'Brien and the Nutshell, also suggest a plan & strategy for doing the research. As with any new legal research project, an excellent starting place can be secondary sources, books and articles that might discuss CIL on your topic. See the sections in this guide for Books, working papers, etc. and Law reviews, journals, articlesUse the other tabs of this research guide to locate any specific sources that you need, e.g., sources for researching the practice of international law,  U.S. practice of international lawtreatiescase law/jurisprudenceinternational organizations, etc.

Research strategies & sources

Selected books & articles on custom & state practice