1993: Bielefeld
1994: Utrecht, Bielefeld
1995: Krippen, Bielefeld
1996: Bielefeld, Luminy (CIRM), Bohmte, Trondheim, Geiranger
1997: Kiev, Essen, Torun, Oberwolfach (MFO)
1998: Murcia, Bielefeld
1999: Ioannina, Oberwolfach (MFO), Prague
2000: Oberwolfach (MFO), Bielefeld, Beijing, Isle of Thorns
2001: Budapest, Nordfjordeid (Sophus Lie conference center), Bielefeld
2002: Trondheim, Toronto (Fields Institute)
2003: Lisbon, Hamburg
2004: Queretaro, Patzcuaro, Luminy (CIRM), Uppsala
2005: Beijing, Beijing (Sino-German Science Center)
2006: Trieste (ICTP), Metz, Bielefeld, Guanajuato (CIMAT), Paderborn
2008: Bielefeld, Banff (BIRS), Bielefeld, Mexico City
2009: Paderborn, Bad Driburg
2010: Trieste (ICTP), Bad Honnef (PBH), Tokyo, Banff (BIRS)
2011: Bielefeld
2012: Cologne, Banff (BIRS), Bielefeld, Teheran (IPM)
2013: Chemnitz
2017: Bielefeld
2018: Bielefeld
2020: Berlin, ICRA 2020 Trieste (online)
4/1996 University of Torun
3/1997 University of Torun
3/1998 Mathematical Institute of UNAM, Mexico City
2/2001 University of Torun
9/2002 Mathematical Institute of UNAM, Mexico City
3/2004 Mathematical Institute of UNAM, Mexico City
3/2005 Mathematical Institute of UNAM, Mexico City and Morelia
9/2006 Mathematical Institute of UNAM, Mexico City and Morelia
Fall 2007 Guest Professor at NTNU Trondheim
9/2009-9/2010 University of Bielefeld
10-12/2010 Research guest of the Max Planck Institute for Mathematics, Bonn
3/2011-3/2013 Researcher at the Università degli Studi di Verona
7-9/2011 Research guest of SFB 701 at the University of Bielefeld
4/2012 (one week) Research guest at the University of Bonn
6/2012 (1/2 month) Research guest at UNAM, Mexico City
7-9/2012 Research guest (SPP 1388) at the University of Bielefeld
4/2013-3/2014 Subst. Professor Algebra, University of Technology Chemnitz
9/2014 (2 weeks) Research guest (SPP 1388) at the University of Bielefeld
3-8/2015 Guest Professor at the University of Szczecin
7-9/2015 Research guest at the University of Bielefeld
11/2015-5/2016 Research guest at Nagoya University
3/2016 (2 weeks) Research guest at USTC in Hefei
3/2017 FernUniversität in Hagen
4-9/2017 University of Münster (subst. position)
6/2017 (1 week) Research guest at Università degli Studi di Verona
10-12/2017 FernUniversität in Hagen
1/2018-6/2019 University of Bonn, Mathematical Institute
9/2018 (3 days) SISSA, Trieste
3/2019 (1 month) Research guest at Università degli Studi di Verona
7/2019 (10 days) Research guest at Università degli Studi di Verona
10/2019-3/2020 Guest Professor at Technische Universität Berlin
4/2020-9/2020 Researcher at Technische Universität Berlin
10/2020-3/2021 Guest Professor at Technische Universität Berlin
4/2021-9/2021 Researcher at Technische Universität Berlin
10/2021-3/2022 Guest Professor at Technische Universität Berlin
4/2022-9/2022 Researcher at Technische Universität Berlin
10/2022-3/2023 Guest Professor at Technische Universität Berlin
4/2023-9/2023 Researcher at Technische Universität Berlin
5/2023 (15 days) Research guest at Università degli Studi di Verona
10/2023-3/2024 Guest Professor at Technische Universität Berlin
(in alphabetical order without multiplicities)
Bielefeld, Bonn, Chemnitz, Hefei, Mexico City, Morelia, Nagoya, Padova, Paris, Shizuoka, Szczecin, Torun, Trondheim, Verona