3 IZA Discussion Papers
IZA Discussion Paper No. 6466
published in: Journal of Labor Economics, 2016, 34(4), 945 - 978
IZA Discussion Paper No. 3960
published in: Journal of European Economic Association, 2009, 7 (2–3), 1–12
IZA Discussion Paper No. 1367
published in: Labour Economics, 2009, 16 (2), 149-160