63 IZA Discussion Papers
IZA Discussion Paper No. 1450
revised version published in: Economic Journal, 2008, 118(531), 1354-1384
IZA Discussion Paper No. 1242
published in: Journal of Economic Growth, 2005, 10 (3), 229-270
IZA Discussion Paper No. 964
published in: Structural Change and Economic Dynamics, 2006, 17 (2), 127-147