Author(s):
1. Branka Ružičić, University of Banja Luka, Faculty of Technology, Republic of Srpska, Bosnia and Herzegovina
2. Dragana Grujić, Faculty of Technology Banja Luka, Republic of Srpska, Bosnia and Herzegovina
3. Blanka Škipina, Faculty of Technology Banja Luka, Republic of Srpska, Bosnia and Herzegovina
4. Ana Velimir, University of Banja Luka, Republic of Srpska, Bosnia and Herzegovina
5. Mladen Stančić, Faculty of Technology Banja Luka, Republic of Srpska, Bosnia and Herzegovina