U.S. Citizenship and Immigration Services. (2012). Tarjetas de educación cívica para el examen de naturalizacíon. U.S. Dept. of Homeland Security, U.S. Citizenship and Immigration Services : For sale by the Supt. of Docs., U.S. G.P.O..
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)U.S. Citizenship and Immigration Services. Tarjetas De Educación Cívica Para El Examen De Naturalizacíon. [Washington, D.C.]: U.S. Dept. of Homeland Security, U.S. Citizenship and Immigration Services : For sale by the Supt. of Docs., U.S. G.P.O., 2012.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)U.S. Citizenship and Immigration Services. Tarjetas De Educación Cívica Para El Examen De Naturalizacíon. U.S. Dept. of Homeland Security, U.S. Citizenship and Immigration Services : For sale by the Supt. of Docs., U.S. G.P.O., 2012.