1. Centre for Social Investigation, Nuffield College, University of Oxford, Oxford, UK
2. Faculty of Management, Economics and Social Sciences, The Institute of Sociology and Social Psychology, University of Cologne, Cologne, Germany
3. Department of Sociology and URPP Social Networks, University of Zurich, Zurich, Switzerland
4. University of Manchester, Manchester, UK
5. Institute of Psychology, University of Lausanne, Lausanne, Switzerland
6. Institute of Social Sciences, University of Lisbon, Lisboa, Portugal
7. Institute of Political Science, University of Giessen, Giessen, Germany