States often regard themselves as bound by treaty rules which have developed under customary international law, even though many of the treaties themselves have not been ratified. The Law of the Sea Convention, for instance, has generated new customary rules which modified the 1958 Geneva Conventions.;These and other issues are dealt with systematically in this handbook on the relations between written and unwritten international law. It contains tables of treaties, statutes and ""travaux preparaties"" and tables of cases.