| 1995 February-April: George Mason University, Fairfax, Va, USA. |
| 1996 August: George Mason University, Fairfax, Va, USA. |
| 1997 Jenuary 20--February 5: George Mason University, Fairfax, Va, USA. |
| 2001 February 22-- March 10: George Mason University, Fairfax, Va, USA. |
| 2002 February 18--March 5: State University of Gent, Belgium. |
| 2002 June 2--10: State University of Gent, Belgium. |
| 2002 November 17--24: Charles University of Prague, Czech Republic. |
| 2003 March--April: George Mason University, Fairfax, Va, USA. |
| 2004 February 23--27: State University of Gent, Belgium. |
| 2004 May 16--27 : George Mason University, Fairfax, Va, USA. |
| 2005 August 3--31 : George Mason University, Fairfax, Va, USA. |
| 2006 April 3--13 : George Mason University, Fairfax, Va, USA. |
| 2006 November 20--26: Charles University of Prague, Czech Republic. |
| 2007 April--May: Chapman University, Orange, CA, USA. |
| 2007 September 6--7: State University of Gent, Belgium. |
| 2008 July17-- August 29: Chapman University, Orange, CA, USA. |
| 2008 November 9--14 : State University of Gent, Belgium. |
| 2009 August 02--07: State University of Gent, Belgium. |
| 2009 October 08-- November 28 : Chapman University, Orange, CA, USA. |
| 2010 April 02 -08 : Charles University of Prague, Czech Republic. |
| 2010 October 15-22: Istituto Politecnico Nacional a Mexico City, Mexico. |
| 2010 October 22 --november 20: Chapman University, Orange, CA, USA. |