424 IZA Discussion Papers
IZA Discussion Paper No. 279
published in: Labour Economics, 2005, 12 (3), 379-406
IZA Discussion Paper No. 179
published in: American Economic Review, 2004, 94 (4), 944-963
IZA Discussion Paper No. 98
IZA Discussion Paper No. 83
published in: Economic Journal, 2001, 111 (471), C120-C134