XXI^st International Conference on Geometry, Integrability and Quantization Varna, Bulgaria, 3-8 June 2019 (with Vladimir Pulov, Rutwig Campoamor-Stursberg and Akira Yoshioka)

XX^th International Conference on Geometry, Integrability and Quantization Varna, Bulgaria, 2-7 June 2018 (with Akira Yoshioka)

XIX^th International Conference on Geometry, Integrability and Quantization Varna, Bulgaria, 2-7 June 2017 (with Guowu Meng and Akira Yoshioka)

XVIII^th International Conference on Geometry, Integrability and Quantization Varna, Bulgaria, 3-8 June 2016 (with Guowu Meng and Akira Yoshioka)

XVII^th International Conference on Geometry, Integrability and Quantization Varna, Bulgaria, 5-10 June 2015 (with A. Ludu and Akira Yoshioka)

XVI^th International Conference on Geometry, Integrability and Quantization Varna, Bulgaria, 6-11 June 2014 (with A. Ludu and Akira Yoshioka)

XV^th International Conference on Geometry, Integrability and Quantization Varna, Bulgaria, 7-12 June 2013 (with A. Ludu and Akira Yoshioka)

EUROMECH Colloquium 535: Similarity and Symmetry Methods in Solid Mechanicsa, Varna, Bulgaria, 06-09 June 2012 (with Jean-Franc¸ois Ganghoffer)

Mini-Symposia: Mechanics of Biological Membranes within ESMC, Graz, Austria, 09-13 July 2012 (with Jean-Fran¸cois Ganghoffer)

XIV^th International Conference on Geometry, Integrability and Quantization Varna, Bulgaria, 8-13 June 2012 (with A. Ludu and Akira Yoshioka)

XIII^th International Conference on Geometry, Integrability and Quantization Varna, Bulgaria, 3-8 June 2011 (with G.Vilasi and Akira Yoshioka)

Interntional Workshop on Complex Structures, Integrability and Vector Fields Sofia, Bulgaria, 13-17 September 2010 (with Kouei Sekigawa, Vladimir Gerdjikov and Yasuo Matsushita)

XII^th International Conference on Geometry, Integrability and Quantization
Varna, Bulgaria, 4-9 June 2010 (with G.Vilasi and Akira Yoshioka)

XI^th International Conference on Geometry, Integrability and Quantization
Varna, Bulgaria, 5-10 June 2009 (with G.Vilasi and Akira Yoshioka)

Tenth International Conference on Geometry, Integrability and Quantization
with spetial sessions on Topics in General relativity and Deformation Quantization
Varna, Bulgaria, 6-11 June 2008 (with G.Vilasi and Akira Yoshioka)

Ninth International Conference on Geometry, Integrability and Quantization
Varna, Bulgaria, 8-13 June 2007 (with M. de Leon)

Eighth International Conference on Geometry, Integrability and Quantization
Varna, Bulgaria, 9-14 June 2006 (with M. de Leon)

Seventh International Conference on Geometry, Integrability and Quantization
Varna, Bulgaria, 2-10 June 2005 (with A. Hirshfeld and M. de Leon)

Sixth International Conference on Geometry, Integrability and Quantization
Varna, Bulgaria, 3-10 June 2004 (with A. Hirshfeld)

Fifth International Conference on Geometry, Integrability and Quantization
Varna, Bulgaria, 5-12 June 2003 (with A. Hirshfeld)

Fourth International Conference on Geometry, Integrability and Quantization
Varna, Bulgaria, 6-15 June 2002 (with G. Naber)

Third International Conference on Geometry, Integrability and Quantization
Varna, Bulgaria, 14-23 June 2001 (with G. Naber and H. Pedersen)

Second International Conference on Geometry, Integrability and Quantization
Varna, Bulgaria, 7-15 June 2000 (with G. Naber)

International Conference on Geometry, Integrability and Quantization
Varna, Bulgaria, 1-10 September 1999 (with G. Naber)

Fourth International Workshop on Complex Structures and Vector Fields,
Varna, Bulgaria 3-10 September 1998 (with S. Dimiev and K. Sekigawa)

Geometry  and  Mathematical  Physics  Conference, Zlatograd, Bulgaria
August 28 - September 1  1995 (with V. Tsanov)

XIII Workshop on Geometric Methods in Physics, Bialowieza, Poland
9-15 July 1994 (with J.-P Antoine, S. Ali, W. Lisiecki and A. Odzijewicz) 

XII Workshop on Geometric Methods in Physics, Bialowieza, Poland
1-7 July 1993 (with J.-P Antoine, S. Ali, W. Lisiecki and A. Odzijewicz) 

XI Workshop on Geometric Methods in Physics, Bialowieza, Poland
7-14 July 1992 (with S. Ali  and  A.  Odzijewicz)