Columbia subject headings:
Harvard subject headings:
Europe--Economic policy--Congresses.
Mercantile system--Europe--Congresses.
Mineral industries--Europe--Congresses.
Mineral industries--History--Congresses.
Miners--Europe--History--Congresses.
Princeton subject headings:
Europe--Economic policy--Congresses.
Mercantile system--Europe--Congresses.
Mineral industries--Europe--Congresses.
Mineral industries--History--Congresses.
Miners--Europe--History--Congresses.