7Ahonji, J. and D. Card, 1991, "The Effects of Immigration on the Labor Market Outcomes of Less-skilled Natives", in Immigration, Trade, and the Labor Market, ed. by J. Abowd and R. Freeman, University of Chicago Press.
8Arellano, M. and O. Bover, 1995,"Another L~ok at the Instrumental Variable Estimation of Error-components Models", Journal of Econometrics, vol.68, pp.29-51.
9Augustine, J. K., 1998, "The Impact of Immigration on the United States Economy", Lanham, MD: University Press of America.
10Blundell, R. and S. Bond, 1998, "Initial Conditions and Moment Restrictions in Dynamic Panel Data Models", Journal of Econometrie., vol.87, nn. 115-143.