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Bernardino, Angelo di, ed. Encyclopedia of the Early Church. Translated by A. Wolford. Cambridge: James Clarke & Co., 1992. 2 Volumes.

Ferguson, Everett, ed. Encyclopedia of Early Christianity. New York, NY: Garland Publishing, Inc., 1990.

Fitzgerald, Allan, ed. Augustine Through the Ages: An Encyclopedia. Grand Rapids, MI: William B. Eerdmans Publishing, 1999.

Hillerbrand, Hans, ed. The Oxford Encyclopedia of the Reformation. Oxford: Oxford University Press, 1996. 4 Volumes.