Resources Primary

Note & disclaimer: In order to conduct proper research, it is vital that students not only familiarize themselves with secondary sources (legal doctrine), but also directly consult relevant primary resources, whether case-law, relevant treaty instruments or practice of international or regional organizations. The list of sources on this page is intended to serve as initial guidance for students conducting research in the broader international law domain. The overview is not intended to be exhaustive. A number of collections included in the list can be accessed only within Ghent University and/or only with a proper subscription. This page is reviewed on a periodic basis, also to ensure that links remain up-to-date. Suggestions for additions to the overview can at all times be sent to the GRILI contact persons

a. Highlights – key sources

United Nations Treaty Series (UNTS):

  • Official treaty database of the United Nations (cf. Art. 102 UN Charter). Largest collection of treaties  (in all international law domains; both bilateral and multilateral). Also offers up-to-date information on participation in treaties (ratifications etc.), lists of reservations, objections and declarations etc.
  • for the texts of treaties that have not yet been published in the UNTS, see 'Texts of Recently Depostied Multilateral Treaties'

International Law Commission (ILC):

  • texts, instruments and final reports of the International Law Commission


UN Official Documents System (ODS):

  • covers all types of official United Nations documentation (e.g., resolutions of the General Assembly or Security Council, letters to the UNSC, verbatim records of UNGA and UNSC meetings,…)
  • Each type of documentatin has a specific UN document code

United Nations Bibliographic Information System (Unbisnet):

  • In addition to a bibliographic database containing records for all United Nations documents, selected materials from the specialized agencies, and books and journals held by the library, users may search in special databases for voting records and speech records.

International Legal Materials (ILM):

  • contains the full texts of important treaties and agreements, judicial and arbitral decisions, national legislation, international organizations resolutions, and other documents
  • published every month
  • available at Ghent University through Hein Online

American Society of International Law Electronic Research Guide (ERG) and Electronic System for International Law (EISIL)

  • ERG: Systematically updated and continuously expanded, the ERG is designed to be used by students, teachers, practitioners, and researchers as a self-guided tour of relevant, quality, up-to-date online resources covering important areas of international law. The ERG also serves as a ready-made teaching tool at graduate and undergraduate levels.
  • EISIL: free online database that organizes and provides links to, and useful information on, web resources covering the full spectrum of international law.

International Law Reports (ILR):

  • The International Law Reports is the only publication in the world wholly devoted to the regular and systematic reporting in English of decisions of international courts and arbitrators as well as judgments of national courts. Since the Reports began in 1922, under the title of the Annual Digest of Public International Law, over 10,000 cases have been reported in full or digest form.
  • Available in print at Ghent University (RBIB)

Oxford Reports on International Law:

  • Over 5.500 case reports on public international law cases of international courts, domestic courts and ad hoc tribunals. Case reports contain the full text of each decision, headnote, as well as analytical commentary and English translations of a number of key non-English decisions.

International Crimes Database (ICD):

  • comprehensive database on international crimes adjudicated by national, as well as international and internationalized courts. In addition to case law on international crimes, the website incorporates general background information about international crimes, scholarly as well as news articles, working papers (ICD Briefs) and relevant links to other useful databases/websites on this topic

ECOLEX - 'the gateway to environmental law'

  • database operated jointly by FAO, IUCN and UNEP providing the most comprehensive, global source of information on environmental law. Contains treaties, legislation, court decisiosn and references to literature.

b. Treaties, decision-making practice international and regional organizations and related

Treaties per field:


United Nations:


Regional organizations (and related): treaties and decision-making practice (selection):


Historical treaties:


National treaty publications:

c. Case-law

International courts and tribunals, and related:


Regional Courts and Tribunals:

d. Custom: state practice and opinio juris

Mapping relevant state practice and opinio juris to ascertain the existence and/or scope of a rule of customary international law can be a complex undertaking.

Many ‘national’ international law journals/yearbooks publish overviews of state practice. Examples include the American Journal of International Law, the revue belge de droit international, the German Yearbook of International Law and many others. See the general international law journals listed under the heading ‘secondary sources’.

In addition, below are a list of useful sources:

ICRC Customary database:

  • Database of relevant practice in the field of the law of armed conflict brought together by the International Committee of the Red Cross. Served as the basis for the ICRC Customary Law Study, identifying 161 rules of customary international law. Updated on a regular basis.

Digest of State Practice – Journal on the Use of Force and International Law

  • Unofficial compilation of state practice and opinio in the realm of the law on the use of force

Digest of United States Practice in International Law:

  • Official publication of the US State Department, providing a period overview of US practice in public and private international law

Italy’s Diplomatic and Parliamentary Practice on International Law

  • Scholarly initiative, compiling relevant statements by representatives of the Italian government on issues of international law