5 IZA Discussion Papers
IZA Discussion Paper No. 17421
IZA Discussion Paper No. 17043
IZA Discussion Paper No. 9587
published in: IZA Journal of Labor Policy, 2016, 5: 19
IZA Discussion Paper No. 4917
published in: Research in Labor Economics, 2011, 32, 227-256
IZA Discussion Paper No. 4310
revised version published in: Journal of Public Economics, 2012, 96 (3-4), 279-294