1. Aiyar , S. 2001 Growth theory and convergence across Indian states a panel study T. Callen P. Reynolds C. Towe India at the Crossroads Sustaining Growth and Reducing Poverty
2. Bajpai , N. Sachs , J. 1996
3. Barro , R. J. Lee , J.-W. 2010
4. Convergence;Barro;Journal of Political Economy,1992