144 IZA Discussion Papers
IZA Discussion Paper No. 154
published in: Economic Journal, 2002, 112 (482), 854-893
IZA Discussion Paper No. 94
published in: Labour Economics, 2009, 9 (2), 143-186
IZA Discussion Paper No. 91
published in: M. Lechner, F. Pfeiffer (eds.), Econometric Evaluation of Labour Market Policies, Heidelberg: Physica, 2001, 43-58
IZA Discussion Paper No. 30
published in: Journal of Comparative Economics, 1999, 27 (1), 61-89