Columbia subject headings:
Harvard subject headings:
Cartography--Europe--History--Congresses.
Harbors--Europe--History--Congresses.
Navigation--History--Congresses.
Shipbuilding--Europe--History--Congresses.
Ships--Europe--History--Congresses.
Princeton subject headings:
Cartography--Europe--History--Congresses.
Harbors--Europe--History--Congresses.
Navigation--History--Congresses.
Shipbuilding--Europe--History--Congresses.
Ships--Europe--History--Congresses.