Author(s):
1. Dušan Petković, Faculty of Mechanical Engineering in Niš, Serbia
2. Goran Radenković, Faculty of Mechanical Engineering in Niš, Serbia
3. Vladislav Blagojević, Faculty of Mechanical Engineering in Niš, Serbia
4. Predrag Živković, Faculty of Mechanical Engineering in Niš, Serbia
5. Ivan Ćirić, Faculty of Mechanical Engineering in Niš, Serbia