APA

Gies F., Gies J., . (1987). Marriage and the family in the Middle Ages. New York: Harper & Row, Publishers.

Chicago

Gies Frances, Gies Joseph, . 1987. Marriage and the family in the Middle Ages. New York: Harper & Row, Publishers.

Harvard

Gies F., Gies J., . (1987). Marriage and the family in the Middle Ages. New York: Harper & Row, Publishers.

MLA

Gies Frances, Gies Joseph, . Marriage and the family in the Middle Ages. New York: Harper & Row, Publishers. 1987.