144 IZA Discussion Papers
IZA Discussion Paper No. 849
IZA Discussion Paper No. 749
published in: Danish Economic Journal, 2006, 144 (2), 18-42
IZA Discussion Paper No. 702
published in: American Economic Review, 2003, 93 (2), 57-62
IZA Discussion Paper No. 296
published in: Journal of Population Economics, 2003, 16 (4), 755-786