Columbia subject headings:
Church--History of doctrines--Middle Ages, 600-1500.
Innocent III, Pope, 1160 or 1161-1216.
Harvard subject headings:
Church history--Middle Ages, 600-1500
Innocent III, Pope, 1160 or 1161-1216
Princeton subject headings:
Church--History of doctrines--Middle Ages, 600-1500.
Innocent III, Pope, 1160 or 1161-1216.