1 Institute of Sectoral Economics and Methodology, Faculty of Economics and Business, University of Debrecen, Debrecen 4032, Hungary. popp.jozsef@econ.unideb.hu.
2 Institute of Sectoral Economics and Methodology, Faculty of Economics and Business, University of Debrecen, Debrecen 4032, Hungary. rakos.monika@econ.unideb.hu.
3 Institute of Business Economics, Faculty of Economics and Business, University of Debrecen, Debrecen 4032, Hungary. zoltangabnai@gmail.com.
4 Institute of Sectoral Economics and Methodology, Faculty of Economics and Business, University of Debrecen, Debrecen 4032, Hungary. balogh.peter@econ.unideb.hu.
5 Institute of Sectoral Economics and Methodology, Faculty of Economics and Business, University of Debrecen, Debrecen 4032, Hungary. antal.gabriella@econ.unideb.hu.
6 Institute of Business Economics, Faculty of Economics and Business, University of Debrecen, Debrecen 4032, Hungary. bai.attila@econ.unideb.hu.