This guide is intended for students and reasearchers studying public international law at the University of Oxford, although students and researches from any field may find it useful.
Use this guide to find out about sources and commentary for treaties and international conventions, including ebooks, ejournals, and databases.
Article 38(1) of the Statute of the International Court of Justice tells the court to decide cases before it by applying
"(a) international conventions, whether general or particular, establishing rules expressly recognised by the contesting States;
(b) international custom ....
(c) the general principles of law recognised by civilised nations
(d).... judicial decisions and the teachings of the most highly qualified ... as subsidiary means for the determination of the rules of law."
As a starting point for current rules of treaty interpretation see Vienna Convention on the Law of Treaties 1155 UNTS 331 (Entered into force on 27 January 1980) See link below.
The Oxford Handbook of United Nations Treaties by 
The Sources of International Law by 