1. a IESE Business School, Camino del Cerro del Águila , 3 E – 28023, Madrid, Spain
2. b Technische Universiteit Eindhoven, School of Industrial Engineering , PO Box 513, Pav. F4 NL – 5600 MB, Eindhoven, Netherlands
3. c School of Technology, Institute for Business Engineering, University of Applied Sciences of Northwestern Switzerland , Promenade 26, CH – 5200 Brugg, Switzerland