Columbia subject headings:
Commerce--History--Medieval, 500-1500--Congresses.
Communication--Europe--History--To 1500--Congresses.
Conference papers and proceedings.
Navigation--Europe--History--To 1500--Congresses.
Sea-power--Europe--History--To 1500--Congresses.
Harvard subject headings:
Commerce--History--Medieval, 500-1500--Congresses.
Communication--Europe--History--To 1500--Congresses.
Conference papers and proceedings.
Navigation--Europe--History--To 1500--Congresses.
Sea-power--Europe--History--To 1500--Congresses.
Princeton subject headings:
Commerce--History--Medieval, 500-1500--Congresses.
Communication--Europe--History--To 1500--Congresses.
Navigation--Europe--History--To 1500--Congresses.
Sea-power--Europe--History--To 1500--Congresses.