1. Lublin University of Technology, Nadbystrzycka 38A, 20-618 Lublin, Poland
2. Pope John Paul II State School of Higher Vocational Education, Sidorska 95/97, 21-500 Biała Podlaska, Poland
3. Institute of Physics, Maria Curie-Skłodowska University, Pl. M. Curie-Skłodowskiej 1, 20-031 Lublin, Poland