Columbia subject headings:
Harvard subject headings:
Germany, Northern--History--To 1500--Congresses.
Middle Ages--Congresses
Nobility--Germany, Northern--History--To 1500--Congresses.
Princeton subject headings:
Germany, Northern--History--To 1500--Congresses.
Middle Ages--Congresses.
Nobility--Germany, Northern--History--To 1500--Congresses.