Columbia subject headings:
Church history--Middle Ages, 600-1500--Sources.
Europe--Church history--600-1500--Sources.
Harvard subject headings:
Church history--Middle Ages, 600-1500--Sources.
Europe--Church history--600-1500.--Sources.
Princeton subject headings:
Church history--Middle Ages, 600-1500--Sources.
Europe--Church history--600-1500--Sources.