Columbia subject headings:
Harvard subject headings:
Mineral industries--Latin America--History--Congresses.
Mineral industries--Spain--History--Congresses.
Mines and mineral resources--Latin America--Bibliography.
Mines and mineral resources--Latin America--History--Congresses.
Mines and mineral resources--Spain--Bibliography.
Mines and mineral resources--Spain--History--Congresses.
Princeton subject headings:
Mineral industries--Latin America--History--Congresses.
Mineral industries--Spain--History--Congresses.