The gateway to the Middle Ages :
France and Britain.
APA Citation
Duckett, E. Shipley. (1961). The gateway to the Middle Ages: France and Britain. [Ann Arbor]: University of Michigan Press.
MLA Citation
Duckett, Eleanor Shipley. The Gateway to the Middle Ages: France And Britain. [Ann Arbor]: University of Michigan Press, 1961.
Warning: These citations may not always be complete (especially for serials).