Columbia subject headings:
Harvard subject headings:
Crusades--Congresses
Europe--Relations--Islamic Empire--Congresses.
Franks--Middle East--History--Congresses.
Islamic Empire--Relations--Europe--Congresses.
Latin Orient--History--Congresses.
Mediterranean Region--History--Congresses.
Middle East--History--Congresses.
Princeton subject headings:
Crusades--Congresses.
Europe--Relations--Islamic Empire--Congresses.
Franks--Middle East--History--Congresses.
Islamic Empire--Relations--Europe--Congresses.
Latin Orient--History--Congresses.
Mediterranean Region--History--Congresses.
Middle East--History--Congresses.