Duignan, B. (2010). The executive branch of the federal government: Purpose, process, and people. Britannica Educational Pub., in association with Rosen Educational Services.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Duignan, Brian. The Executive Branch of the Federal Government: Purpose, Process, and People. New York: Britannica Educational Pub., in association with Rosen Educational Services, 2010.
توثيق جمعية اللغة المعاصرة MLA (الطبعة الثامنة)Duignan, Brian. The Executive Branch of the Federal Government: Purpose, Process, and People. Britannica Educational Pub., in association with Rosen Educational Services, 2010.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.