Professional Experience

Teaching Assistant, Mathematics, University of Nebraska (Lincoln), 1951-1953.

Teaching Assistant, Mathematic, University of Minnesota (Minneapolis), 1953-55.

Instructor, Mathematics, Hamline University, 1955-1956.

Instructor (1956-57), Assistant Professor (1957-58), Associate Professor (1958-62),  Professor (1962-95), Professor Emeritus and Mathematician in Residence (1995--), Concordia College (Moorhead MN). Chairperson 1963-70; Research Professor 1970-71; Sigurd and Pauline Prestegaard Mundhjeld Professor of Mathematics, 1988-95.

Visiting Assistant Professor, Mathematics, University of Nebraska, 1960-61.

Mathematician, Remington Rand Univac, St. Paul, summer 1958.

Mathematician/Analyst, Control Data Corporation, Minneapolis, summers 1960, 1961, 1962; consultant 1960-63.

Directed NSF-supported programs of Undergraduate Research Participation, Concordia College, summers 1963, 1964, 1966.

Consultant, NSF and U. S. Agency for International Development, at Summer Institutes for High School and College Mathematics Teachers in India, summers 1968, 1969.

Visiting Scholar (NSF Postdoctoral Faculty Fellow), University of California, Berkeley, 1966-67 (12 months).

Visiting Professor/Scholar, Mathematisches Institut der Universität zu Köln, Germany, 1973-74 (12 months).

Visiting Professor, Department of Pure and Applied Mathematics, Washington State University, Pullman, 1980-81.

Bush Research Scholar, Concordia College, 1983-84.

Visiting Professor, Institut für Statistik, Ökonometrie und Operations Research, Universität Graz, Austria, 1987-88; Sept. 1990--Jan. 1991; Jan.--May 1994; Oct.--Dec. 1997.

Director of USA Mathematical Olympiad Training Session, and Leader of USA Delegation to the International Mathematical Olympiad, summers 1988, 1989, 1990.

Centennial Research Scholar, Concordia College, summers 1992, 1993, 1994, 1995.