Article 2(a) of the Vienna Convention on the Law of Treaties defines a treaty as an international agreement “governed by international law, whether embodied in a single instrument or in two or more related instruments and whatever its particular designation.”
Treaty research is essentially a three step process:
Bluebook Rule 21.4.5(a) (i) and (ii) requires that you cite to one of the following official U.S. treaty sources (in order of preference). If the agreement has not appeared in one of these official sources, cite an unofficial source (see boxes below).
According to Bluebook rule 21.4.5(b), for agreements to which the United States is not a party, cite one source published by an international organization, if therein. If not, cite the official source of one signatory, if therein. If the treaty is not found in a signatory's treaty source, cite an unofficial treaty source.
The following are unofficial treaty compilations that provide access to the texts of treaties, both historical and current.