1. Institute of Metals and Technology, Lepi pot 11, 1000 Ljubljana, Slovenia
2. Bitola, Faculty of Technology and Technical Sciences, St. Kliment Ohridski University, Veles, Dimitar Vlahov bb, 1400, Veles, Macedonia
3. Center for Plasma Technologies - Plasma, Veljko Vlahovic 18, 1000 Skopje, Macedonia