1. International Conference on Engineering Optimization (EngOpt2018), Lisbon, Portugal.
  2. International Congress on Industrial and Applied Mathematics, Beijing, China.
  3. International Symposium on Mathematical Programming (ISMP-2012), Berlin, Germany.
  4. Workshop on General Algebra (Arbeitstagung Allgemeine Algebra), Dresden, Germany.
  5. Workshop on General Algebra (AAA) and Conference for Young Algebraists (CYA), Потсдам, Германия.
  6. Workshop on Semigroups, Lisbon, Portugal.
  7. International Conference of Mathematics and Computer Science "Congressio-Mathematica”, Olsztyn, Poland.
  8. International Conference “Uniform Distribution Theory”, Slovakia.
  9. Spring Conference of the Union of Bulgarian Mathematicians, Боровец, България.
  10. International Scientific Conference FMNS, Благоевград, България.
  11. Workshop on General Algebra (AAA104), Благоевград, България.