1. El impuesto federal sobre los ingresos para personas físicas. [Washington, D.C.] : Dept. of the Treasury, Internal Revenue Service Journal Online Marcive GPO Government Documents
2. El impuesto federal sobre los ingresos para personas físicas. [Washington, D.C.] : Dept. of the Treasury, Internal Revenue Service Journal Online US Government Documents
3. Your federal income tax for individuals. [Washington, D.C.?] : Dept. of the Treasury, Internal Revenue Service Journal Online Marcive GPO Government Documents
4. Your federal income tax for individuals. [Washington, D.C.?] : Dept. of the Treasury, Internal Revenue Service Journal Online US Government Documents