Mulligan, C. B., & Sala-i-Martin, X. (1999). Gerontocracy, retirement, and social security. National Bureau of Economic Research.
Chicago-viite (17. p.)Mulligan, Casey B., ja Xavier Sala-i-Martin. Gerontocracy, Retirement, and Social Security. Cambridge: National Bureau of Economic Research, 1999.
MLA-viite (9. p.)Mulligan, Casey B., ja Xavier Sala-i-Martin. Gerontocracy, Retirement, and Social Security. National Bureau of Economic Research, 1999.
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