3 IZA Discussion Papers
IZA Discussion Paper No. 7440
published in: Applied Economics, 2015, 47(23), 2413-2429
IZA Discussion Paper No. 6985
published in: Education Economics, 2013, 21 (3), 281-303
IZA Discussion Paper No. 4321
published in: Economics of Education Review, 2012, 31 (5), 619-628