Author(s):
1. Milica Tufegdžić, Academy of Professional Studies Šumadija, Kragujevac, Serbia, Serbia
2. Predrag Dašić, SaTCIP Publisher Ltd., 36610 Vrnjačka Banja i Visoka tehnička mašinska škola strukovnih studija (VTM, Serbia
3. Nevena Tufegdžić, SaTCIP Publisher Ltd, Vrnjačka Banja, Srbija, Serbia