3 IZA Discussion Papers
IZA Discussion Paper No. 12146
IZA Discussion Paper No. 557
published in: Revue de l’IRES, 2005, http://dx.doi.org/10.3917/rdli.049.0093
IZA Discussion Paper No. 153
published in: Journal of the Royal Statistical Society, Series A (Statistics in Society), 2005, 168 (1), 207-231