International Symposium on"Organic Maturation Studies and Fuel Exploration" International Sumposium on Interaction Studies in Nuclei,Mainz,1975 International Symposium on Protein Metabolism and Nutrition International symposium on plastics testing and standardization International Symposium on Dynamic Soil-Structure Interaction International symposium on molecular structure and sepctroscopy Organic maturation studies and fossil fuel exploration International symposium on nonlinear differential equations and nonlinear mechanics 14th national symposium on concrete structure education International Symposium on Flight Test Instrumentation