1. Laboratory for Mathematical Modelling of Wave PhenomenaInstitute for Problems in Mechanical Engineering, Russian Academy of ScienceSt. PetersburgRussia
2. Laboratory of Mathematical PhysicsSt. Petersburg Department of the Steklov Mathematical InstituteSt. PetersburgRussia
3. Department of Mathematical Physics, Faculty of Mathematics and MechanicsSt. Petersburg State UniversitySt. PetersburgRussia