http://repository.hneu.edu.ua/bitstream/123456789/20079/1/2018-%20%D0%9E%D1%82%D0%B5%D0%BD%D0%BA%D0%BE%20%D0%86%20%D0%9F%2C%20%D0%A7%D0%B5%D0%BF%D0%B5%D0%BB%D1%8E%D0%BA%20%D0%9C%20%D0%86.pdf