Author(s):
1. Zoran Janjuš, City Administration, Banja Luka, Republic of Srpska, Bosnia and Herzegovina
2. Aleksandar Petrović, Univeristy of Belgrade, Faculty of Mechanical Engineering, Serbia
3. Aleksandar Jovović, Univeristy of Belgrade, Faculty of Mechanical Engineering, Serbia
4. Radica Prokić-Cvetković, Faculty of Mechanical Engineering, Serbia