1. Institut für Mittelstandsforschung (IfM) Bonn, Bonn, Germany
2. School of Economic Disciplines, University of Siegen, Siegen, Germany
3. Rutgers Advanced Institute for the Study of Entrepreneurship and Development, Rutgers University, Newark, NJ, USA
4. Bertha Centre for Social Innovation & Entrepreneurship, University of Cape Town, Cape Town, Western Cape, South Africa