Columbia subject headings:
Church history--Middle Ages, 600-1500.
Rome (Italy)--Church history--Congresses.
Rome (Italy)--History--476-1420--Congresses.
Harvard subject headings:
Church history--Middle Ages, 600-1500
Rome (Italy)--Church history--Congresses.
Rome (Italy)--Civilization--Congresses.
Rome (Italy)--History--476-1420--Congresses.
Princeton subject headings:
Church history--Middle Ages, 600-1500.
Rome (Italy)--Church history--Congresses.
Rome (Italy)--Civilization--Congresses.
Rome (Italy)--History--476-1420--Congresses.