1. See “The Changing Shape of the Nation’s Income Distribution,” page 9. http://www.census.gov /prod/2000pubs/p60–204.pdf (Accessed: June 10, 2013). See also Hans-Werner Sinn, “Social Insurance, Incentives and Risk Taking,” International Tax and Public Finance, 3, no. 3 (1996), 258–280.
2. See Henry Sanborn, “Pay Differences between Men and Women,” Industrial and Labor Relations Review 17, no. 4 (July 1964), 534–550
3. Francine D. Blau and Lawrence M. Kahn, “Rising Wage Inequality and the U.S. Gender Gap,” American Economic Review 84, no. 2 (May 1994), 23–28. doi: http://www.aeaweb.org /aer/
4. Francine D. Blau and Lawrence M. Kahn, “Gender Differences in Pay,” Journal of Economic Perspectives 14, no. 4 (Fall 2000), 75–99. doi: http://www.aeaweb.org /jep/
5. James J. Heckman, “A Partial Survey of Recent Research on the Labor Supply of Women,” American Economic Review 68, no. 2 (May 1978), 200–207. doi: http://www.aeaweb.org /aer/