4 IZA Discussion Papers
IZA Discussion Paper No. 10880
published in: M. Tsionas (ed.), Panel Data Economics: Empirical Analysis, 2019, 885 - 929
IZA Discussion Paper No. 10448
IZA Discussion Paper No. 6004
published in: Economics of Innovation and New Technology, 2014, 23(1), 25-48.
IZA Discussion Paper No. 4784
published in: Technological Forecasting and Social Change, 2011, 78 (4), 575-590