Hayes, C. J. H., & Clark, F. F. (1966). Medieval and early modern times: The age of Justinian to the eighteenth century. Macmillan ; Collier Macmillan Pub..

Hayes, Carlton J. H., and Frederick F. Clark. Medieval and Early Modern Times: The Age of Justinian to the Eighteenth Century. New York : London: Macmillan ; Collier Macmillan Pub., 1966.

Hayes, Carlton J. H., and Frederick F. Clark. Medieval and Early Modern Times: The Age of Justinian to the Eighteenth Century. Macmillan ; Collier Macmillan Pub., 1966.