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International Law: Custom and State Practice

Includes resources for general research on International Law topics

Primary Sources of International Law

Custom and State Practice

Publications of the US State Department and International yearbooks can provide evidence of customary international law. International yearbooks provide surveys of the practices of specific States and/or geographical areas within the international law arena. Many Intergovernmental Organizations also publish yearbooks. 

US Department of State

International Yearbooks

International Yearbooks

Other Helpful sites