1. MAPP - Department of Management, Aarhus BSS, Aarhus University, Aarhus, Denmark
2. Walbusch-Stiftungslehrstuhl Für Multi-Channel-Management, Schumpeter School of Business and Economics, Bergische Universität Wuppertal, Wuppertal, Germany
3. School of Economics and Business, Norwegian University of Life Sciences (NMBU), Ås, Norway
4. Department of Informatics, University of Zurich, Zürich, Switzerland