APA način citiranja (7. izdanje)
Keen, M., Kim, Y. K., & Varsano, R. (2006). The "flat tax(es)": Principles and evidence. International Monetary Fund, Fiscal Affairs Dept..
Čikaški stil citiranja (17. izdanje)
Keen, Michael, Yitae Kevin Kim, i Ricardo Varsano. The "Flat Tax(es)": Principles and Evidence. Washington, D.C.: International Monetary Fund, Fiscal Affairs Dept., 2006.
MLA način citiranja (9. izdanje)
Keen, Michael, et al. The "Flat Tax(es)": Principles and Evidence. International Monetary Fund, Fiscal Affairs Dept., 2006.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.