Author(s):
1. Slobodan Gnjato, University of Banja Luka, Faculty of Natural Sciences and Mathematics, Republic of Srpska, Bosnia and Herzegovina
2. Tatjana Popov, University of Banja Luka, Faculty of Natural Sciences and Mathematics, Republic of Srpska, Bosnia and Herzegovina
3. Goran Trbić, Republic of Srpska, Bosnia and Herzegovina

Abstract