1. Saint-Petersburg State University,Department of Modelling in Social and Economical Systems,St. Petersburg,Russia
2. Saint-Petersburg State University,Faculty of Applied Mathematics and Control Processes,St. Petersburg,Russia
3. Russian State Hydrometeorological University,Department of Higher Mathematics and Physics,St. Petersburg,Russia
4. Stavropol State Agrarian University,Department of Physics,Stavropol,Russia
5. Stavropol State Agrarian University,Department of Financial Management and Banking,Stavropol,Russia