The Development of Christendom during its first centuries

The Christian Tradition: A History of the Development of Doctrine, Volume 2: The Spirit of Eastern Christendom (600-1700)

Landmarks: The development of the soul during the cycle of the year

The Ottoman Threat and Crusading on the Eastern Border of Christendom during the 15th Century: 48 (East Central and Eastern Europe in the Middle Ages, 450-1450, 48)

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