1. Threshold externalities in economic development;Azariadis;Quarterly Journal of Economics,1990
2. Economic growth in a cross-section of countries;Barro;Quarterly Journal of Economics,1991
3. Convergence across states and regions;Barro;Brookings Papers on Economic Activity,1991
4. Convergence;Barro;Journal of Political Economy,1992
5. Productivity growth, convergence and welfare: What the long run data show;Baumol;American Economic Review,1986