Cita APA (7a ed.)
Krey, A. C. (1929). Medieval Foundations of western civilization.
Cita Chicago Style (17a ed.)
Krey, August Charles. Medieval Foundations of Western Civilization. 1929.
Cita MLA (9a ed.)
Krey, August Charles. Medieval Foundations of Western Civilization. 1929.
Precaución: Estas citas no son 100% exactas.