Introduction to Modern Economic Growth Revera-Batiz, Luis A and Paul M Romer (1991) “Economic Integration and Endogeous Growth.“ Quarterly Journal of Economics, 106, pp 531-555 Romer, Paul M (1986) “Increasing Returns and Long-Run Growth.“ Journal of Political Economy, 94, pp 1002-1037 Romer, Paul M (1987) “Growth Based on Increasing Returns Due to Specialization.“ American Economic Review, 77, pp 56-62 Romer, Paul M (1990) “Endogenous Technological Change.“ Journal of Political Economy, 98(part I), pp S71-S102 Romer, Paul M (1993) “Idea Gaps and Object Gaps in Economic Development.“ Journal of Monetary Economics, 32, pp 543-573 Rosenberg, Nathan (1976) Perspectives on Technology Cambridge University Press, Cambridge Rosenzweig, Mark and Kenneth Wolpin (1980) “Testing the Quantity-Quality Fertility Model: The Use of Twins as a Natural Experiment.” Econometrica, 48, pp 227-240 Rybczynski, T M (1955) “Factor Endowment and Relative Commodity Prices.“ Economica, 22, pp 336-341 Sachs, Jeffrey and Andrew Warner (1997) “Fundamental Source of Long-Run Growth.” American Economic Association Papers and Proceedings, 87, pp 184188 Sachs, Jeffrey (2001) “Tropical Underdevelopment.” NBER Working Paper #8119 Saint -Paul, Gilles (2003) “On Market and Human Evolution.” CEPR Discussion Paper No 3654 Sala-i-Martin, Xavier (1997) “I Just Ran Two Million Regressions.“ American Economic Review, 87, pp 178-183 Samuelson, Paul A (1958) “An Exact Consumption-Loan Model of Interest with or without the Social Contrivance of Money.“ Journal of Political Economy, 66, pp 467-482 Samuelson, Paul A (1965) “A Theory of Induced Innovation along KennedyWeiszacker Lines.” Review of Economics and Statistics, 47(4), pp 343-356 Schmookler, Jacob (1966) Invention and Economic Growth Harvard University Press, Cambridge, MA 848