Columbia subject headings:
Harvard subject headings:
Canons, Cathedral, collegiate, etc.--Europe--History.
Church and state--Catholic Church--History
Church and state--Europe--History
Church history--Middle Ages, 600-1500
Princeton subject headings:
Canons, Cathedral, collegiate, etc.--Europe--History.
Church and state--Catholic Church--History.
Church and state--Europe--History.
Church history--Middle Ages, 600-1500.