Cita APA (7th ed.)

Bullough, D. (1973). The age of Charlemagne (2nd ed.). P. Elek.

Cita Chicago (17th ed.)

Bullough, Donald. The Age of Charlemagne. 2nd ed. London: P. Elek, 1973.

Cita MLA (9th ed.)

Bullough, Donald. The Age of Charlemagne. 2nd ed. P. Elek, 1973.