Kursk PasovetsYuliyaM. Kursk State University, Radishcheva str., 33, Kursk, 305000, Russian Federationyulia_pasovets@mail.ru Read more about Pasovets Yuliya M. ChuikovOlegЕ. Kursk State University, Radishcheva str., 33, Kursk, 305000, Russian Federationchuikov-ru@mail.ru Read more about Chuikov Oleg Е.