I. M. Horban Ivan Franko National University of Lviv Ukraine
I. V. Shydlovskyy https://orcid.org/0000-0002-1003-2562 Ivan Franko National University of Lviv Ukraine
O. S. Hnatyna https://orcid.org/0000-0002-7178-5541 Ivan Franko National University of Lviv Ukraine
N. A. Pisulinska Physical-mechanics Institute of NAS of Ukraine Ukraine
M. A. Senyk Ivan Franko National University of Lviv Ukraine