5 IZA Discussion Papers
IZA Discussion Paper No. 10451
IZA Discussion Paper No. 9256
published in: Journal of Labor Economics, 2019, 37 (1), 139 - 185
IZA Discussion Paper No. 5714
IZA Discussion Paper No. 4069
published in: Economics of Education Review, 2011, 30 (2), 215-227
IZA Discussion Paper No. 426
revised version published in: Labour Economics, 2007, 14(6), 926-937