| Postgraduale Lehrgänge/Summer School | Sonstiges |  | 09/1984 | 09/1984 | <b>Rings and Geometry</b>, Nato Advanced Study Institute, Istanbul, Turkey | 
| Postgraduale Lehrgänge/Summer School | Sonstiges |  | 07/2004 | 07/2004 | Sommerschule: <b>Scuola Estiva di Geometria Combinatoria e Ottimizzazione 2004 "Giuseppe Tallini", Brescia, Italien</b>. | 
| Postgraduale Lehrgänge/Summer School | Sonstiges |  | 09/2009 | 09/2009 | Vorlesungen im Rahmen der Kooperationsgruppe "Finite Projective Ring Geometries" am Zentrum für Interdisziplinäre Forschung der Universität Bielefeld, Deutschland | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | 11th International Conference on Geometry and Its Applications, Varna | 09/2013 |  | A Note on Segre Varieties in Characteristic Two | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | Workshop & Summer School on Finite Semifields, Padova | 09/2013 |  | A Note on Segre Varieties in Characteristic Two | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | Combinatorics 2010, Verbania | 06/2010 |  | Diameter Preserving Surjections in the Geometry of Matrices | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | Plenary Lecture, Centre for Interdisciplinary Research (ZiF), University of Bielefeld | 10/2009 |  | Dual Polar Spaces and the Geometry of Matrices III | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | Invited Lecture, Enter Cartography, University of Applied Arts, Vienna | 06/2011 |  | Einhundert Projektionsprobleme - Ein Programm zum Zeichnen von Karten | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | 10th Congress of the Austrian Mathematical Society - DMV Jahrestagung | 09/1981 |  | Embedding of Desarguesian Projective Spaces | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | Invited Lecture, 'Arbeitsgemeinschaft Geometrie', University of Hamburg | 06/2012 | 06/2012 | Geometrie der zyklischen Untermoduln über den Ternionen | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | Invited Lecture, Modern Algebra and Its Applications, Rustaveli State University, Batumi | 09/2010 |  | Geometries on sigma-Hermitian Matrices | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | Invited Lecture, University of Warmia and Mazury, Olsztyn | 11/2010 |  | Geometries on sigma-Hermitian Matrices | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | Invited Lecture, University of Padova, Vicenza | 02/2010 |  | Matrix Spaces and Grassmannians | 
| Wissenschaftliche Konferenz/Symposium | Sonstiges |  | 09/2007 | 09/2007 | Member of International Scientific Committee. 8th International Conference on Geometry and Applications, Varna, Bulgaria. | 
| Wissenschaftliche Konferenz/Symposium | Sonstiges |  | 08/2001 | 08/2001 | Member of International Scientific Committee. <b>5th International Conference on Geometry and Applications, Varna, Bulgaria</b>. | 
| Wissenschaftliche Konferenz/Symposium | Sonstiges |  | 09/2003 | 09/2003 | Member of International Scientific Committee. <b>6th International Conference on Geometry and Applications, Varna, Bulgaria</b>. | 
| Wissenschaftliche Konferenz/Symposium | Sonstiges |  | 09/2005 | 09/2005 | Member of International Scientific Committee.7th International Conference on Geometry and Applications, Varna, Bulgaria. | 
| Wissenschaftliche Konferenz/Symposium | Sonstiges |  | 01/2008 | 10/2008 | Member of Organising Committee, 33th South German Colloquium on Differential Geometry, TU Vienna, Austria | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | Invited Lecture, University of Warmia and Mazury, Olsztyn | 09/2011 |  | Mutually Inscribed and Circumscribed Simplices - Where Möbius Meets Pauli | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | Conference on Geometry - Theory and Applications, Vorau | 06/2011 |  | Möbius Pairs and Pauli Operators | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | 10th International Conference on Geometry and Applications, Varna | 09/2011 |  | On Möbius Pairs of Simplices | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | Invited Lecture, 6th Podlasie Conference on Mathematics, Bialystok | 07/2014 |  | Preserver Problems in Geometry | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | Invited Lecture, Combinatorics 2012, Perugia | 09/2012 |  | Projective Ring Lines and Their Generalisations | 
| Wissenschaftliche Konferenz/Symposium | eingeladene_r Sprecher_in | Finite Geometries, Fourth Irsee Conference, Irsee | 09/2014 |  | Tetrads of Lines Spanning |