Authors
Ihor Virt
Drohobych State Pedagogical University, Ukraine
Piotr Potera
Institute of Materials Engineering, College of Natural Sciences, University of Rzeszow, Poland
Grzegorz Wisz
Institute of Materials Engineering, College of Natural Sciences, University of Rzeszow, Poland
Andrzej Dziedzic
Institute of Physics, College of Natural Sciences, University of Rzeszow, Poland
Bogumił Cieniek
Institute of Materials Engineering, College of Natural Sciences, University of Rzeszow, Poland
Ivan Lopatynskyi
Lviv Polytechnic National University, Lviv, Ukraine
Marian Frugynskyi
Lviv Polytechnic National University, Lviv, Ukraine