1. University of Dunaujvaros, Institute of Engineering, Department of Mechanical Engineering, Tancsics M. u. 1/A, 2400 Dunaujvaros, Hungary
2. Budapest University of Technology and Economics, Department of Automotive Technologies, Stoczek J. u. 6, H-1111 Budapest, Hungary
3. Technical University of Kosice, Faculty of Electrical Engineering and Informatics, Department of Physics, Komenského park 2 041 20 Košice, Slovakia
4. Eötvös Loránd University, Department of Matrials Physics, Pazmany Peter setany 1/a., 1117 Budapest, Hungary