00290nam a2200097Ia 4500008004100000082002000041100002200061245006000083260002900143700002000172220204s9999    xx            000 0 und d  a678-477bRIN-B1  aCotter,  Robert J 0aRing forming polymerizations. Pt B1. Heterocyclic rings  aNew YorkbAcademicc1972  aMatzner, Markus