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: