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International Law: General Sources: Sources of IL, I.C.J. Statute, U.N. Charter

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.

Outline

Databases

This guide provides links to a variety of databases, several of which are limited to NYU Law faculty and students. Information for NYU Law students and faculty on obtaining passwords for Westlaw, Lexis Advance and Bloomberg is available here

Getting started--classics, encyclopedias, databases, etc.

Classics, introductions & other books

Encyclopedias, dictionaries & directories

Websites, databases & research guides

Books, Ebooks, Working Papers, etc.

EBOOKS: HOW TO FIND ONLINE BOOKS

The NYU Law Library and Bobst Library offer many ebook databases.

FINDING BOOKS, EBOOKS, WORKING PAPERS, ETC.

To find books, reporters, codes, treaty collections, etc., start by searching the NYU Law Library's JULIUS catalog using a keyword, author, title, or ISBN/ISSN search.

MORE TOOLS FOR FINDING BOOKS & EBOOKS

See also the note on finding ebooks above, and  Getting Started: classics, encyclopedias, databases, etc.

Law reviews, journals, articles

IF YOU ALREADY HAVE A CITATION TO AN ARTICLE

If you have a citation to an article in a particular law review, journal, newspaper, or other periodical, search the title or the ISSN of the publication in this search box:

Journal title


The results of a Journal Title search include print and microform journals in the Law Library and online journals via the NYU Law and Bobst libraries (Westlaw, Bloomberg Law, Lexis+, and many other journal databases). If you don't find the journal in a Journal title search, try searching Bobcat to find out if the journal is in print or microform at the NYU Bobst Library. To find articles by topic, author, date, etc., see the box below.

FINDING ARTICLES by topic, author, date, etc.

Article Finders include online indexes (lists of articles) and databases of full-text articles/journals. You can search article finders by keywords, subjects, author names, dates, etc. Westlaw, LexisAdvance, Bloomberg Law, and HeinOnline are "article finders," but for more PDFs, more journals (including more non-law journals) and more years of the journals in the "big four," you should also search additional relevant Article Finders available through JULIUS. The Article Finders listed below tend to be useful for foreign, comparative and international law topics. Depending upon your topic, you may want to search additional Article Finders, Interdisciplinary databases and relevant non-law databases available through the NYU Bobst Library. See also the guide Finding Articles which lists many more tools for finding articles. 

Working papers

News, blogs & paper/note topics

Finding paper & note topics

Abbreviation dictionaries & citation manuals

Abbreviation dictionaries & citation manuals

Sources of IL, I.C.J. Statute, U.N. Charter

Statute of the International Court of Justice, Art. 38(1) sources of international law

The Statute of the International Court of Justice appears at the end of the Charter of the United Nations. Cite: Statute of the International Court of Justice, art. 38,  ¶ 1.

1. The Court, whose function is to decide in accordance with international law such disputes as are submitted to it, shall apply:
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.

Other sources that may be relevant to your research

For selected books that may discuss the sources of international law, see the Getting started tab in this guide.

Treaties

Treaty research materials & FAQs

Treaty research materials & FAQs

This guide uses the term "treaty" as a shortcut for the various terms used for treaties, conventions, agreements, etc. The "depositary" of a treaty holds the official text and provides updated status and other information about the treaty. The depositary might provide a website, a finding tool or other resources to answer your research questions about the treaty. If a convention is monitored by an expert committee or body, the website of the monitoring entity is a great place to start for the text of the convention, explanation, status information about the treaty, required reports from states parties, documents relating to any complaint or dispute settlement procedure, publications, news, etc.. Selected examples include:

More in-depth research may require several types of treaty research materials:

  • full-text sources in print and/or online that provide the full text of treaties
  • "finding tools," including print or online indexes, lists, and status tables, and also online websites and databases, that provide citations and vital information about a treaty and its status
  • travaux préparatoires, the preparatory materials from the drafting, negotiation and adoption of a treaty
  • commentaries, which print the treaty article-by-article with expert commentary on each article, possibly with citations to the travaux préparatoires and/or subsequent IGO documents, reports, domestic implementing laws, cases, or dispute settlements that show the implementation and application of a treaty. 

The FAQs on this page are typical treaty research questions. Each question points to the treaty research materials that can help you answer that FAQ.

Treaty research FAQs and strategy

Treaty research FAQs and strategy, continued

  • FAQ 2:  What treaties are relevant to my research?
    Use the same finding tools listed in the bullet of FAQ 1 entitled IF YOU DO NOT HAVE A CITATION. In addition, read books and articles on your topic to determine what the experts say are the treaties relevant to your area of law. 
     
  • FAQ 3:  What are the "vital statistics" of the treaty: signatories, parties, dates of signing & entry into force, status, is it still in force, has it terminated, has it been amended, etc.? 
    Use the same finding tools listed in the bullet of FAQ 1 entitled IF YOU DO NOT HAVE A CITATION.
     
  • FAQ 4:  Are there background materials ("travaux préparatoires," e.g., drafts, letters, documents, reports, etc.) or States Party materials from the drafting, negotiation and adoption of the treaty that might indicate how it was intended to operate? 
    See Commentaries & travaux préparatoires
     
  • FAQ 5:  Is there an article-by-article expert/scholarly commentary on the treaty which might set forth the history, implementation or application of the treaty with citations to "travaux préparatoires," IGO documents, domestic laws, cases, etc.?
    See Commentaries & travaux préparatoires.

  • FAQ 6:  Are there subsequent IGO documents, reports, domestic implementing laws, cases, or dispute settlements that show the implementation and application of the treaty? 

Selected books & research guides

Selected books on the law of treaties

See also Books, Ebooks, Working papers, etc. and law reviews, journals, articles.

Search Julius by title to determine if the library has print copies of the ebooks listed below.

Bluebook treaty sources

Bluebook UNOFFICIAL treaty sources: Rule 21.4.5(c)

I.L.M., International Legal Materials, is the preferred unofficial source. Published every two months by the American Society of International Law, I.L.M. reprints selected new treaties, laws, cases, etc. 

Finding citations, signatories, parties, & status. Finding all treaties on a subject.

Finding treaty citations, signatories, parties, & status. Finding all treaties on a subject.

United Nations Charter

Text, citation, commentary

United Nations & League of Nations treaties

About United Nations treaties

U.N.T.S. United Nations Treaty Series 1946-, Bluebook Rule 21

Finding UN and League of Nations treaty citations, signatories, parties, & status. Finding all treaties on a subject.

General multilateral & historical treaty sources & IGO treaty sources

General multilateral & historical treaty sources & searching tools

IGO treaty sources

Selected special subject treaty sources

If the U.S. is a party

If the U.S. is a party

Bilateral treaties & treaty sources for countries other than the U.S.

Finding bilateral treaty citations, signatories, parties, status, and texts. Finding bilateral treaties on a subject.

To identify a country's published treaty source(s)

Commentaries & travaux préparatoires (drafting history)

What are travaux préparatoires & what are commentaries?

Travaux préparatoires, also referred to as "negotiating history" and "drafting history," are the preparatory materials from the drafting, negotiation and adoption of a treaty, and might include documents, reports, minutes, drafts, and other materials. A state party's materials on the drafting, negotiation and domestic ratification, adoption and/or implementation of a treaty might also be relevant to your research. All of these are the primary sources, or "raw materials," for researching the history of a treaty. See Vienna Convention on the Law of Treaties, arts. 31-32, May 23, 1969, 1155 U.N.T.S. 331, 8 I.L.M. 679.

commentary is generally a book or article that reprints the articles of a treaty in numerical order. Following each article is the author's analysis of that article, often including citations to the travaux préparatoires and/or to the jurisprudence/case law that has applied or interpreted the article. 

Finding travaux préparatoires and commentaries

As with all legal research, you might be able to jump start your research by looking for secondary sources that will set forth the history of the treaty negotiation and adoption and ideally will cite the negotiating materials. For some treaties, books, articles or IGO websites and databases may provide an article-by-article guide to the history and/or application of the treaty, with expert or scholarly analysis on that article and citations to the relevant travaux préparatoires and perhaps to subsequent jurisprudence/case law applying the treaty. Collections of some or all of the travaux préparatoires have been published for some treaties (see examples in the next box).

To search library catalogs and article finders for books and articles, do keyword searches using some combination of (1) the treaty title or words from the treaty title, (2) words from the treaty subject and (3) words such as travaux préparatoires, commentary, guide, documents, documentary, history, negotiation, analysis, and final record. You should also do a subject search for the name of the treaty.

If you do not find a commentary on your treaty or a collection of or guide to the travaux préparatoires, you can try searching for relevant materials yourself. For example, if a convention was negotiated by a conference of nations under the auspices of the United Nations, then look at summaries of UN codification efforts, such as the Analytical Guide to the Work of the International Law Commission. You can also search pleadings and judgments in international law cases to see whether and how attorneys and courts have relied upon the travaux préparatoires from the treaty (or subject area) that you are researching. Kuehl and O'Brien, International Legal Research in a Global Community 58 (2018). Ultimately, your research may require that you do searches directly in the universe of the documents of the U.N. or other organization that sponsored the treaty negotiation or is concerned with the subject matter of the treaty. See International Organizations

For national materials on the drafting, negotiation and domestic ratification/adoption of a treaty, you will need to search sources for that country, e.g., U.S. Senate Treaty documents or other congressional publicationsnational yearbooks of international law and other sources of state practice. An example is Reams and Schultz, The North American Free Trade Agreement (NAFTA): Documents and Materials Including a Legislative History of the North American Free Trade Agreement Implementation Act: Public Law 103-182 (Oceana,2003), available in HeinOnline. See also Foreign Law by Jurisdiction and U.S. ratification & implementation of treaties; Presidential statements, proclamations, etc.

UPDATE: À la Recherche des Travaux Préparatoires: An Approach to Researching the Drafting History of International Agreements, Globalex, by Jonathan Pratter, lists sources for selected treaties, as well as methodology for looking for travaux préparatoires.

See also specific subject tabs, e.g. Human Rights.

The next box lists examples of commentaries and collected travaux préparatoires.

Selected commentaries and collected travaux préparatoires

This list is not exhaustive. See the preceding box for advice on searching for additional commentaries.
TIP: If you find your treaty or convention in HeinOnline, click on the icon for Display ScholarCheck statistics to see if any articles or cases have cited it. There are three search engines for finding treaties and conventions in HeinOnline:

The Oxford Public International Law database (Browse>Book titles) has a number of the OUP commentaries, for example: 

Soft law

If it looks like a treaty, but...

...you can't find it in standard treaty tools and collections, it may be "soft law" and not a treaty. Soft law is non-binding, but may indicate the objectives and principles that states are willing to support publicly. Examples often come from the economic, environmental, social, and human rights areas and may include General Assembly resolutions, declarations, e.g., the Universal Declaration of Human Rights, codes of conduct, guidelines, programs of action, and documents resulting from international conferences. See "Soft law," in Parry & Grant Encyclopaedic Dictionary of International Law (3d ed. 2009).

Sources of soft law

Texts of "soft law" might be located in documents of the IGO or other body that sponsored the international conference from which the document emerged, in the publications and official documents of the organization or on its website, or in books, articles or websites covering the topic.

See 
Books, Ebooks, Working papers, etc. 
Law reviews, journals, articles

United States treaties

Research guides

Research guides

Official treaty sources

Choosing the right official source: Rule 21.4.5(a)(i) & (ii)

To find a citation to an official treaty source, use Treaties in Force, updating it with the tools listed here.

NOTE about the dates covered by the print editions of the Bluebook official sources for U.S. treaties:
U.S.T. and T.I.A.S. are no longer published in print. For the dates covered by the print publications, see the box "Post-1949 official treaty sources" on this page and the Dept. of State, Office of Treaty Affairs page Finding Agreements. PDFs of later T.I.A.S. slip treaties are on the Dept. of State website and in HeinOnline


If your treaty is not in U.S.T. or T.I.A.S., it might be in one or more of the other official sources listed in Bluebook Rule 21.4.5(a)(i) and (ii). Those other sources are included in the other two boxes on this page, Pre-1950 official treaty sources and Post-1949 official treaty sources. Those lists also include a few more official government publications that, although not listed in the Bluebook, might contain the text or indicate the status of a treaty before it is ratified, e.g., Senate Executive Reports and presidential communications to the Senate. 

See also Bluebook & other unofficial sources and Presidential statements, proclamations, etc.

Post-1949 official treaty sources

Pre-1950 official treaty sources

Unofficial treaty sources

Bluebook UNOFFICIAL treaty sources: Rule 21.4.5(c)

I.L.M., International Legal Materials, is the preferred unofficial source. Published every two months by the American Society of International Law, I.L.M. reprints selected new treaties, laws, cases, etc. 

Treaties in Force: Finding citations, signatories, parties, & status. Finding all treaties on a subject.

About United States Treaties in Force

Treaties in Force: A List of Treaties and Other International Agreements of the United States in Force on January 1 [year] provides official status of in force U.S. treaties as of the date on the volume; citations to TIAS and UST; lists of treaties by countries and subjects; indication of reservations, understandings and declarations


TIF is updated only once a year. The Dept. of State issued a 2014 supplement to 2013 instead of a complete new edition. The TIF updating and search tools provide later citations, later status information, lists of later treaties or pending treaties on a topic or with a certain country, etc.

Updating Treaties in Force: Finding citations, signatories, parties, & status. Finding all treaties on a subject.

Updating TIF: Finding citations, signatories, parties, & status. Finding all treaties on a subject.

Presidential statements, proclamations, etc.

U.S. implementing legislation, cases & legislative history

Finding any U.S. implementing law & cases

First, determine if the treaty required U.S. implementing legislation. See U.S. Treaty Implementation, in Heidi Frostestad Kuehl & Megan A. O'Brien, International Legal Research in a Global Community at 37, which recommends that books and articles on the treaty can be a good starting place for determining if there is domestic implementing legislation, and if so, to look for citations to the law and cases. If you think there is implementing legislation, another good starting point is look up the treaty name in the Popular Name Table of, or indexes to, U.S.C.A. and also consult any cases listed in the annotations to U.S.C.a.

Customary IL & state practice

Customary international law & state practices tab

The Customary international law & state practice tab contains the following tabs:

Research strategies & selected books

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

Sources for researching state practice of international law

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

U.S. practice of international law

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., sources for researching the practice of international lawtreatiescase law/jurisprudenceinternational organizations, etc.

For historical details and background, use The SHAFR Guide Online: An Annotated Bibliography of U.S. Foreign Relations since 1600, Brill Online. The Bibliography covers all historical periods, geographical areas and major themes. Materials listed include government documents, biographies, monographs, book chapters, journal articles, websites, etc.  

U.S. Department of State

The Digest of United States practice

The Department of State Office of the Legal Advisor publishes the Digest to provide a historical record of the views and practice of the government in public and private international law over a period of time. The editors cite, excerpt or reprint documents from the State department and other agencies and departments. The title of the series has changed over the years. 
 
Finding documents excerpted or cited in the digests:  The Digest now provides citations to internet or other publicly available sources of the full text. Starting with 1989, for documents excerpted or cited in the Digest that are not readily available in hard copy or electronic format, the Dept. of State website provides links to the full text (click on the link for the year). See also Foreign Relations of the United States, in the next box on this page 

FRUS, Foreign Relations of the United States, & other document sources

Foreign Relations of the United States (FRUS) contains "the official documentary historical record of major U.S. foreign policy decisions and significant diplomatic activity." It includes declassified documents from the presidential libraries, Depts of State and Defense, NSC, CIA, other agencies, and from private papers of officials. Starting with 1952 FRUS is arranged by presidency and geographically and topically within each presidency. Coverage begins with 1861. It is published with many years delay. 

General principles

Books & introductions

Case law/jurisprudence, I.C.J., etc.

Case law/jurisprudence tab

General tools for finding cases on international law

Find cases on international law by topic, etc.

No single reporter or source contains all international cases and awards.The sources listed below are in addition to other specialized sources for specific courts, tribunals or topics such as international trade disputes or human rights that are listed in other research guides and in the guide International Law: Specialized Sources.

Books, working papers, etc. and law reviews, journals, articles on your topic might cite relevant cases or awards. See also Practice of international law by other countries (yearbooks, etc.).

For the titles of a country's case reporters and similar publications, consult the Bluebook or another citation manual. See also Foreign Law by Jurisdiction, NYU Law Library.

How to Find Cases in English Translation, Revisited, Lyonette Louis-Jacques   

See also
I.C.J. and P.C.I.J.
U.S. cases on international law

Citators: Find citations to a case, plus related cases & analysis

News & recent developments

I.C.J. and P.C.I.J.

P.C.I.J. Permanent Court of International Justice, 1922-1946

The following are shelved in Compact Shelves with call numbers beginning JX1971 5A6... and also available online at the links below. 

Publications of the Permanent Court of International Justice = Publications de la Cour Permanente de Justice Internationale

Series A: Judgments, orders, etc. on contentious cases,1923-1930
Series B: Advisory Opinions, etc.,1922-1930 
Series A/B: Judgments, Orders and Advisory Opinions, 1931-1940
Series C: Acts and Documents Related to Judgments and Advisory Opinions
Series D: Acts and Documents Related to the Organization of the Court (Statute, Rules, etc.)
Series E: Yearbook of the Court
Series F: Bibliography and Indexes

Finding I.C.J. & P.C.I.J. cases by topic, etc.

U.S. cases on international law

Finding U.S. cases on international law

Teachings of the most highly qualified publicists

Teachings of the most highly qualified publicists

Some books, articles and commentary by experts might be deemed to be "the teachings of the most highly qualified publicists. For a discussion of factors that might be used for making this determination, see, e.g., 

  • Kuehl & O'Brien, International Legal Research in a Global Community, at 93-96.
  • Sivakumaran, The Influence of Teachings of Publicists on the Development of International Law, 66 International and Comparative Law Quarterly 1 (2017)
  • Helmerson, Finding “the Most Highly Qualified Publicists”: Lessons from the International Court of Justice, 30 European Journal of International Law 509 (2019)

For selected writings and to find others, see 
Getting started--classics, etc. 
Books, Ebooks, Working papers, etc. 
Law reviews, journals, articles
Expert & scholarly organizations

International Law Commission

Publications of the ILC

ILC documents, A/CN.4/--

International organizations

Research strategy

Start with websites and publications where the organization has summarized its work, e.g., Analytical Guide to the Work of the Int’l Law Commission, Yearbook of the United Nations or the Repertoire of the Practice of the Security Council. Also consult books and articles on your topic. As you read, note the document symbols for relevant documents so that you can use them to locate the full text of the documents. Also consult the research guides, websites and databases below for more information, including how to find official documents from various international organizations. 

See also, Jim Church, Access to Information and International Government Organization Archives, 47:4 DttP, Documents to the People (2019).

Selected websites & databases

Expert & scholarly organizations

Selected Expert & Scholarly Organizations

The reference works, draft conventions, codifications, reports, journals, yearbooks, or other publications of scholarly, professional and other expert organizations might be used as "subsidiary sources" of international law ("the teachings of the most highly qualified publicists of the various nations") under Article 38(1) of the Statute of the International Court of Justice. They might also state what the author considers to be state practice, opinio juris or general principles, and they might be cited in legal arguments and judicial decisions. See Winer, Archer & Louis-Jacques, International Law Legal Research 239-241 (2013).

Below are links to the organizations cited as examples in the Winer book at 242-251:

Statistics

Statistics related to international law and international affairs

Westlaw, Lexis+, HeinOnline, & Bloomberg Law

International & foreign materials in the major U.S. legal databases

See also Websites, databases & research guides.

International content in the major U.S. legal databases varies.The topic "International" under the U.S. portion of a database generally contains U.S. materials on international law and not foreign or international content, which generally is located as described below. Check the database's scope notes (usually an "i" icon) to determine specific content and dates covered. 

Other research guides

Other research guides

International Law: Specialized Sources

Research guide

Foreign law

Foreign Law Resources