Education: Universities of Leiden and Utrecht, Mathematics and Physics, 1940--49 (with war-time interruptions) Ph.D. in Mathematics, Leiden, 1949 Regular professorships (Mathematics) Technical University Delft (Netherlands), 1951-(Jan)1953 University of Wisconsin (Madison), (Feb)1953--64 (Chairman, Program in Applied Mathematics and Engineering Physics, 1956--61) University of California San Diego (La Jolla), 1964--74 (Chairman, Dept of Mathematics, 1971--73) University of Amsterdam, 1974--(Jan)93 (Director, Math. Institute, 1980--83) Temporary and visiting positions Mathematical Center, Amsterdam, 1947--49 Purdue University, Acad. yrs 1949--51 University of Michigan, Summer 1950 Stanford University, Acad. yr 1961--62 and several summers Claremont Graduate School, Sep. 1969 -- Jan. 1970 University of Oregon, Summer 1970 Imperial College, London, Acad. yr 1970--71 Technical University Eindhoven, Summer 1971 California Institute of Technology, Spring 1988 Bar-Ilan University (Israel), Spring 1992 Honors and special assignments Reynolds' award for outstanding teaching of future engineers, University of Wisconsin, 1956 Elected Fellow Amer. Assoc. Adv. Science, 1961 Chairman, American Mathematical Society Summer Research Institute on "Entire functions and related parts of analysis", La Jolla, 1966 Member, KNAW (Royal Netherlands Academy of Arts and Sciences) since 1975 Honorary doctorate, University of Gothenburg (Sweden), 1978 Chairman, Wiskundig Genootschap (Netherlands Mathematical Society), 1982--84 Lester R. Ford Prize (1987) and Chauvenet Prize (1989) for mathematical exposition (Mathematical Association of America) Elected honorary member, Netherlands Math. Soc., 1998 Honorary member, Amer. Math. Society Editor or co-editor of various mathematical journals and of conference proceedings at one time or another