124 IZA Discussion Papers
IZA Discussion Paper No. 765
improved version available as IZA Discussion Paper No. 2124
IZA Discussion Paper No. 374
published in: International Economic Review, 2006, 47 (3), 895-936
IZA Discussion Paper No. 119
IZA Discussion Paper No. 39
published in: Journal of Labor Economics, 2000, 18 (3), 353-376