65 IZA Discussion Papers
IZA Discussion Paper No. 811
published in: Research in Labor Economics, 2007, 26, 299-336
IZA Discussion Paper No. 657
IZA Discussion Paper No. 536
IZA Discussion Paper No. 533
published in: Torben Andersen and Per Molander (eds,): Alternatives for Welfare Policy: Coping with Internationalisation and Demographic Change, Cambridge, 2003, 255 - 275