1. Ghent University , Ghent , Belgium
2. Ghent University , Ghent , Belgium ; Research Foundation – Flanders , Brussels , Belgium ; University of Antwerp , Antwerp , Belgium ; Université catholique de Louvain , Louvain-la-neuve , Belgium ; Institute of Labor Economics (IZA) , Bonn , Germany ; Global Labor Office (GLO) , Stanford , USA ; IMISCOE , Rotterdam , Netherlands