164 IZA Discussion Papers
IZA Discussion Paper No. 1536
published as: 'Peer Effects in Welfare Dependence: Quasi-experimental Evidence" in: Journal of Human Resources, 2009, 44(3), 799–825
IZA Discussion Paper No. 651
final version published in: Journal of Institutional and Theoretical Economics, 2004, 160 (2), 232-42
IZA Discussion Paper No. 621
published in: Journal of Theoretical Biology, 2007, 247, 397- 412,
IZA Discussion Paper No. 73