Columbia subject headings:
Christianity and other religions--Congresses.
Church history--Middle Ages, 600-1500--Congresses.
Europe--Church history--Congresses.
Middle East--Religion--Congresses.
Harvard subject headings:
Christianity and other religions--Congresses
Church history--Middle Ages, 600-1500--Congresses.
Europe--Church history--Congresses.
Middle East--Religion--Congresses.
Princeton subject headings: