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Introduction to International Law - Sources in the UM Law Library: Home

This guide to international legal research is designed primarily for students with little or no experience in doing research in international law.

Sources of International Law

International law consists of a body of rules governing the relations between states. Its historical function was the preservation of peace and it is currently related to foreign policy, power balance and economic relationships. International law is traditionally divided into two branches, public and private.

Public international law regulates the relations of states among themselves and with each other's nationals. Increasing amounts of public international law are being codified under such diverse headings as international trade, criminal extradition, admiralty and international aviation law, immigration and naturalization law, conduct during wartime and human rights.

Private international law (in this country frequently called “conflict of laws”) determines where and by whose law controversies involving more than one jurisdiction are to be resolved, as well as how foreign judgments are enforced. Private international law applies to individuals as well as corporations and other business entities. It also has been referred to as "transnational law."

The Statute of the International Court of Justice (Article 38) defines the sources of international law as follows:

  1. Treaties, covenants and agreements between nations.
  2. Traditional law of nations, as established by customary practice and generally accepted.
  3. Principles of international law.
  4. International adjudications, tribunals and arbitrations.
  5. Classic commentaries and digests of international law.
  6. Law developed by international organizations and reflected in their documentation.
  7. Law of foreign relations (including diplomatic and consular law).
  8. Municipal (i.e., domestic or internal) law of individual states relating to international matters.

General Texts

To obtain an overview of international law, students should consult a general treatise. Written by scholars and authorities, they define the state of the law and also influence its development. The following are classic authoritative texts in the field:

Oppenheim, L. Oppenheim's International Law, edited by R. Jennings and Arthur Watts. 9th ed. 1992.

Brierly, J.L. The Law of Nations. 6th ed. 1963.

Schwarzenberger, G. Manual of International Law. 6th ed. 1976.

O'Connell, D.P. International Law. 2nd ed. 1970.

Von Glahn, S. Law Among Nations. 7th, rev. ed., 1996.

Steiner, H.J. & Vagts, D. Transnational Legal Problems. 3rd ed. 1986.

Bishop, W.W. International Law: Cases & Materials. 3rd ed 1971.

Henkin, L. International Law: Cases & Materials. 2nd ed. 1987.

Dicey, A. Dicey and Morris on the Conflict Of Laws. 13th ed. 2000.

Kahn-Freund, O. General Problems of Private International Law. 1976.

Ehrenzweig, A. Private International Law. 3 volumes. 1967.

Brownlie, I. Principles of Public International Law. 5th ed. 1998.

Bederman, D. International Law Frameworks 2001.

Janis, M. An Introduction to International Law. 3rd ed. 1999.

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