4 IZA Discussion Papers
IZA Discussion Paper No. 8998
IZA Discussion Paper No. 6473
Economic Journal, 2016, 126, 1238-1263
IZA Discussion Paper No. 5520
revised version published in: Public Choice, 2013, 156(3-4), 653-676
IZA Discussion Paper No. 3902
published in: Public Choice, 2009, 140 (3-4), 379 - 394