Daniel B. Measurement of Tax Progressivity. American Economic Review. September 1977, 67 (4): 747–752. JSTOR 1813408. Internal Revenue Service. [2009-03-27]
Individual income tax rates, from Canada Revenue Agency official site: [1] (页面存档备份,存于互联网档案馆). Quebec has a separate income tax system: 存档副本. [2008年4月1日]