4 IZA Discussion Papers
IZA Discussion Paper No. 7559
IZA Discussion Paper No. 1363
published in: Review of Economic Studies, 2006, 73 (4), 1009-1038
IZA Discussion Paper No. 492
published in: Journal of Public Economics, 2004, 88 (12), 2587-2616
IZA Discussion Paper No. 444
published in: Jonas Agell, Michael Keen and Alfons Weichenrieder (eds.), Labor Market Institutions and Public Regulation, 2004, 63-100