| 1982 - 1988 |
Assistant Professor, Bucknell University |
| 1988 - 1989 |
Sabbatical, Universität Bern |
| 1989 - 1995 |
Associate Professor, Bucknell University |
| 6/1992 |
Guest Professor, Universität Karlsruhe |
| 1995 - |
Professor, Bucknell University |
| 1995 - 1996 |
Sabbatical, Universität Bern |
| 9/1995 |
Member, MSRI, Berkeley California |
| 3/1996 |
Guest Professor, Université de Metz |
| 7/ 1996 - 7/1997 |
Guest Professor, Université de Metz |
| 1/2001 - 1/2004 |
Presidential Professor, Bucknell University |
| 8/2002 |
Guest Professor, Université de Metz |
| 9/2002 - 2/2003 |
Guest Professor, Universität Bern |
