1. Faculty of Economics and Business, University of KU Leuven, Naamsestraat 69, 3000 Leuven, Belgium
2. UNU-MERIT and Maastricht University, Maastricht, The Netherlands
3. Department of Strategy and Innovation, Copenhagen Business School, Kilevej 14A, 2000 Frederiksberg, Denmark
4. Department Innovation Economics and Industrial Dynamics, ZEW – Centre for European Economic Research, L7.1, 68161 Mannheim, Germany