3 IZA Discussion Papers
IZA Discussion Paper No. 2994
published in: Annals of Economics and Statistics, 2013, 111/112, 35-70
IZA Discussion Paper No. 2123
published in: Labour Economics, 2007, 14 (6), 657-970
IZA Discussion Paper No. 1003
published in: Research in Labor Economics, 2010, 30,189-231