1. Institute for Sociology and Social Psychology (ISS), Cologne University, Cologne, Germany
2. Centre for Demographic Research, Catholic University of Louvain, Louvain-la-Neuve, Belgium
3. Fonds de la Recherche Scientifique, Brussels, Belgium
4. Center for Demographic Research, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
5. Department of Social Work and Social Administration, The University of Hong Kong, Pokfulam, Hong Kong