Linear Operators and Approximation / Lineare Operatoren und Approximation: Proceedings of the Conference held at the Oberwolfach Mathematical Research Institute, Black Forest, August 14–22, 1971 / Abhandlungen zur Tagung im Mathematischen Forschungsinstitut Oberwolfach, Schwarzwald, vom 14. bis 22. August 1971

Topics in Modern Operator Theory: 5th International Conference on Operator Theory, Timişoara and Herculane (Romania), June 2–12, 1980