Authors
P. Bragiel
Institute of Physics, Jan Dlugosz University,, Czestochowa, Poland
W. Prochwicz
Institute of Chemistry, Environmental Protection and Biotechnology, Jan Dlugosz University,, Czestochowa, Poland
I. Radkowska
Institute of Physics, Jan Dlugosz University,, Czestochowa, Poland
N. Veeraiah
Physics Department, Acharya Nagarjuna University,, Nagarjuna Nagar, India