1. Department of Economics, Koszalin University of Technology, 75-343 Koszalin, Poland
2. HVL Business School, Western Norway University of Applied Sciences, Røyrgata 6, 6856 Sogndal, Norway
3. Department of Marketing, Management and Finance Institute, WSB Merito University in Gdansk, Al. Grunwaldzka 238A, 80-266 Gdansk, Poland