Institute of Socio-Economic Development of Territories Russian Academy of Sciences, Gorkogo Str., 56A, Vologda, Russia / Department of Applied Mathematics Vologda State University, Vologda, S. Orlova, 6, Russia
Department of Applied Mathematics Vologda State University, Vologda, S. Orlova, 6, Russia
Institute of Problems of Informatics Russian Academy of Sciences, Vavilova str., 44-2, Moscow, Russia