1. Round Table: Discussion on the direct trade among developing countries. Zagreb, Yugoslavia, 12 to 14 September, 1973. Report. 45 S.; 3. Round Table: Financial co-operation among developing countries. Zagreb, Yugoslavia, September 15 to 19, 1975. Proceedings. V,387 S.; 4. Round Table on industrial co-operation among developing countries. Zagreb, September 13-17,1976. Proceedings. XII,179 S.; 5. Round Table: Technical and economic co-operation among developing countries. Zagreb, September 12-16, 1977. Proceedings. VIII,414 S