According to article 38 of the Statute of the International Court of Justice, international law is comprised of:
- international treaties, conventions and their preparatory documents or "travaux preparatoire"
- international judicial decisions and decisions of national courts
- the general principles as codified by the International Law Commission
- custom, as found in newspapers, hansards, government reports, statements at international conferences, national laws
- scholarly writings as found in texts, treatises, articles and commentary
For More detail and links, see the library guide to International Law: http://libguides.uvic.ca/international-law