1. Department of Engineering Management and Enterprise, Faculty of Engineering, Institute of Industrial Process Management, University of Debrecen, Ótemető Str. 2, 4028 Debrecen, Hungary
2. Faculty of Social Sciences, Institute of Economics, Savaria Department of Business Administration, Eötvös Loránd University, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary