Columbia subject headings:
Harvard subject headings:
Community development--Europe--History--Congresses.
Community development--South America--History--Congresses.
Mineral industries--Congresses
Mineral industries--Europe--History--Congresses.
Mineral industries--Social aspects--Europe--History--Congresses.
Mineral industries--Social aspects--South America--History--Congresses.
Mineral industries--South America--History--Congresses.
Mines and mineral resources--Social aspects--Europe--History--Congresses.
Mines and mineral resources--Social aspects--South America--History--Congresses.
Mountain life--Congresses.
Princeton subject headings:
Mineral industries--Congresses.
Mountain life--Congresses.