1. Institute of Chemistry, University of Miskolc, Miskolc-Egyetemváros, H-3515 Miskolc, Hungary
2. Higher Education and Industrial Cooperation Centre, University of Miskolc, Miskolc-Egyetemváros, H-3515 Miskolc, Hungary
3. Ferenc Rákóczi II Transcarpathian Hungarian College of Higher Education, UA-90200 Beregszász, Transcarpathia, Ukraine