Affiliation: | 1.Faculty of Physics and Astronomy, University of Zielona Góra, Szafrana 4a, 65-246, Zielona Góra, Poland ;2.Faculty of Mathematics, Computer Science and Econometrics, University of Zielona Góra, Szafrana 4a, 65-246, Zielona Góra, Poland ;3.National Centre for Nuclear Research, Ho?a 69, 00-681, Warszawa, Poland ; |