Author(s):
1. Jaroslava Budinski-Simendic, Univerzitet u Novom Sadu, Tehnološki fakultet, Novi Sad, Serbia
2. Vojislav Jovanović, PMF Kosovska Mitrovica, Serbia
3. Branka Petković, PMF Kosovska Mitrovica, Serbia
4. Milena Marinovic-Cincovic, University of Belgrade, Vinča Institute of Nuclear Sciences, Serbia, Serbia
5. Suzana Samaržija-Jovanovic, PMF Kosovska Mitrovica, Serbia
6. Gordana Markovic, Tigar A.D., Pirot, Serbia

Final paper