4Finis Welch, In Defense of Inequality, American Economic Review, vol. 89, no 2, 1999, pp. 1-17.
5Tyler Cowen, Why Is Income Inequality in America So Pronounced? Consider Education, The New York Times, May 17, 2007.
6Timothy Aeppel, Economists Gain Star Power; Hot Demand Lifts Salaries, as Elite Universities Seek Big Names, The Wall Street Journal, February 22, 2005 o
8Claudia Goldin, and Lawrence E Katz,The Race Between Education and Technology: The Evolution of U.S. Educational Wage Differentials, 1890 to 2005, NBER Working Paper, no. 12984, 2007.
