366 IZA Discussion Papers
IZA Discussion Paper No. 249
IZA Discussion Paper No. 235
IZA Discussion Paper No. 128
published in: Journal of Econometrics, 2005, 125 (1-2), 53-75
IZA Discussion Paper No. 96
IZA Discussion Paper No. 63
IZA Discussion Paper No. 11
published in: Applied Economics, 2002, 34 (7), 865-876