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A reference service focusing on multilateral treaties concluded by more than two parties, this calendar covers a period of almost 350 years of multilateral diplomacy, from the Peace of Westphalia of 1648 to the end of 1995. It lists chronologically all multilateral treaties concluded during that period, provides information on the location of their printed text in various collections (with parallel citations), adds data on duration, depository arrangements, and status, and provides extensive notes on their amendments, modification, extension, termination and other details.