- University of Minnesota (Minneapolis, Minn.), 1954 (1)
- University of Minnesota (Minneapolis, Minn.), 1960 (1)
- University of Minnesota (Minneapolis, Minn.), 1962 (1)
- University of Minnesota (Minneapolis, Minn.), 1963 (1)
- University of Minnesota (Minneapolis, Minn.), 1964 (1)
- University of Minnesota (Minneapolis, Minn.), 1965 (1)
- University of Minnesota (Minneapolis, Minn.), 1966 (1)
- University of Minnesota (Minneapolis, Minn.), 1966-1967 (1)
- University of Minnesota, Institute for Advanced Study (Minneapolis, Minnesota), 2006 (1)
- University of Minnesota, Institute for Advanced Study (Minneapolis, Minnesota), 2008 (1)
- University of Minnesota, Institute for Advanced Study;University of Minnesota 2004 (1)
- University of Minnesota. Institute for Advanced Study (Minneapolis, Minnesota), 1995 (1)
- University of Minnesota. Institute for Advanced Study (Minneapolis, Minnesota), 1996 (2)
- University of Minnesota. Institute for Advanced Study (Minneapolis, Minnesota), 2002 (1)
- University of Minnesota. Institute for Advanced Study (Minneapolis, Minnesota), 2003 (2)
- University of Minnesota. Institute for Advanced Study (Minneapolis, Minnesota), 2004 (3)
- University of Minnesota. Institute for Advanced Study (Minneapolis, Minnesota), 2005 (3)
- University of Minnesota. Institute for Advanced Study (Minneapolis, Minnesota), 2006 (10)
- University of Minnesota. Institute for Advanced Study (Minneapolis, Minnesota), 2007 (24)
- University of Minnesota. Institute for Advanced Study (Minneapolis, Minnesota), 2008 (21)
