Cita APA (7th ed.)
Tierney, B. (1970). The Middle Ages. Knopf.
Cita Chicago (17th ed.)
Tierney, Brian. The Middle Ages. New York: Knopf, 1970.
Cita MLA (9th ed.)
Tierney, Brian. The Middle Ages. Knopf, 1970.
Atenció: Aquestes cites poden no estar 100% correctes.