1. Department of Management, Technology and Economics Swiss Federal Institute of Technology ETH Zürich Weinbergstr. 56/58 8092 Zürich Switzerland
2. Department of Supply Chain Management The University of Tennessee—Haslam College of Business 916 Volunteer Blvd., SMC #320 Knoxville Tennessee 37996 USA
3. Operations and Supply Chain Management Group EBS Universität für Wirtschaft und Recht Hauptstr. 31 65375 Oestrich‐Winkel Germany