1. Faculty of Economics and Business Administration, Ghent University, Ghent, Belgium
2. OM PARTNERS NV, Koralenhoeve 23, 2160 Wommelgem (Antwerp), Belgium
3. Africa Business School, Mohammed VI Polytechnic University, Rabat, Morocco
4. Edward P. Fitts Department of Industrial and Systems Engineering, North Carolina State University, Raleigh, NC, USA