T. B. Peretyatko https://orcid.org/0000-0002-5769-3050 Ivan Franko National University of Lviv Ukraine
A. A. Halushka https://orcid.org/0000-0002-2638-3113 Ivan Franko National University of Lviv Ukraine
S. P. Gudz Ivan Franko National University of Lviv Ukraine