| Institut or University | from | duration |
| Institut de Physique Nucleaire,
Orsay, France |
May 1988 | 1 month |
| Institute for Nucl. Research and Nucl. Energy,
Sofia, Bulgaria |
Sept. 1989 | 1 month |
| Free University of Amsterdam
and NIKHEF-K, Amsterdam, the Netherlands |
Sept. 1991 | 3 months |
| Kernfysisch Versneller Instituut,
Groningen, the Netherlands, |
Dec. 1991 | 3 months |
| Dipartimento di Fisica dell'Universita
and INFN, Milano, Italy |
March 1993
Oct. 1994 March 1995 Oct. 1995 May 1996 Oct. 1999 March 2000 |
2 months
2 months 2 months 2 months 1 month 1 month 1 month |
| Institut fur Kernphysik,
Technische Universitat, Darmstadt, Germany |
Oct. 1993
May 1994 Apr. 1996 June 1998 |
2 months
2 months 1 month 3 months |
| GSI,
Darmstadt, Germany, |
July 1997 | 1 month |
| Instituto de Fisica,
Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil |
Oct. 1997 | 2 months |
| University of Gent,
Gent, Belgium |
Jan. 1999 | 14 months |
| Ludwig Maximilians Universitat,
Munich, Germany |
May 2000 | 2 months |
| University of the Witwatersrand,
Johannesburg, South Africa |
June 2013
May 2014 |
1 month 1 month |