3 IZA Discussion Papers
IZA Discussion Paper No. 6591
published in: Journal of Happiness Studies, 2013, 14 (4), 1379-1408
IZA Discussion Paper No. 1391
published in: Schriften des Vereins für Socialpolitik, 2006, 313, 39-54.
IZA Discussion Paper No. 1175
published in: Social Indicators Research, 2010, 95 (1), 111-128