1. Department of Political Science, Danish Centre for Studies in Research and Research Policy, Aarhus University , Bartholins Allé 7, Aarhus C DK-8000, Denmark
2. Universitat Oberta de Catalunya , Av. Carl Friedrich Gauss 5, Castelldefels ES-08860, Spain
3. Fraunhofer ISI , Breslauer Str. 48, Karlsruhe DE-76139, Germany