L. V. Bunio Ivan Franko National University of Lviv Ukraine
O. M. Tsvilynjuk Ivan Franko National University of Lviv Ukraine
I. M. Mykiyevych https://orcid.org/0000-0001-6777-5554 Ivan Franko National University of Lviv Ukraine
O. I. Velychko https://orcid.org/0000-0003-3470-5677 Ivan Franko National University of Lviv Ukraine
O. I. Terek https://orcid.org/0000-0003-0230-4166 Ivan Franko National University of Lviv Ukraine