Mulligan, C. B., & Sala-i-Martin, X. (1999). Gerontocracy, retirement, and social security. National Bureau of Economic Research.
Čikaški stil citiranja (17. izdanje)Mulligan, Casey B., i Xavier Sala-i-Martin. Gerontocracy, Retirement, and Social Security. Cambridge: National Bureau of Economic Research, 1999.
MLA način citiranja (9. izdanje)Mulligan, Casey B., i Xavier Sala-i-Martin. Gerontocracy, Retirement, and Social Security. National Bureau of Economic Research, 1999.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.