4 IZA Discussion Papers
IZA Discussion Paper No. 11324
IZA Discussion Paper No. 10613
published in: Quantitative Economics, 2017, 8 (3), 895-927
IZA Discussion Paper No. 7437
published in: Economics of Education Review, 2016, 55, 39-56
IZA Discussion Paper No. 5395
published in: Economics Letters, 2011, 113 (1), 19-22