Interregional meeting of International River Organizations.-- National Symposium on River Basin Development.-- Work of the United Nations International Law Commission.-- Treaty for Amazonian Co-operation becomes operational.-- Meeting of Ministers for Foreign Affairs of the Plate Basin countries.-- Guinea joins the Gambia River Basin Development Organization.-- Uganda joins the Kagera River Basin Organization.-- Transboundary water issues in the Mexican-United States border region.-- Call for documents and participation in the information exchange