1. Høgskulen i Sogn og Fjordane, Postboks 7030, Bergen, Norway;
2. Western Norway Research Institute, Sogndal, Norway;
3. School of Business and Economics, Linnaeus University, Kalmar, Sweden;
4. Department of Management, Marketing and Entrepreneurship, University of Canterbury, Private Bag 4800, Christchurch, New Zealand;
5. Institute of Transport Economics, Gaustadalleen 21, Oslo, Norway;
6. Nottingham University Business School, Jubilee Campus, Nottingham, UK