Citazione Stile APA (7a Edizione)

Billings, H. (1987). Studying the Constitution. D.C. Heath.

Citazione stile Chigago Style (17a edizione)

Billings, Henry. Studying the Constitution. Lexington [u.a.]: D.C. Heath, 1987.

Citatione MLA (9a ed.)

Billings, Henry. Studying the Constitution. D.C. Heath, 1987.