4 IZA Discussion Papers
IZA Discussion Paper No. 12928
published in: Empirical Economics, 2021, 60, 227 - 259
IZA Discussion Paper No. 3642
IZA Discussion Paper No. 2193
published in: Journal of Population Economics, 2011, 24 (1), 141-165
IZA Discussion Paper No. 1138
revised version published in: Journal of Applied Econometrics, 2009, 24 (7) 1095-1116