Columbia subject headings:
Harvard subject headings:
Mineral industries--Portugal--Aljustrel (Beja)--History.
Miners--Labor unions--Portugal--Aljustrel (Beja)--History.
Miners--Portugal--Aljustrel (Beja)--History.
Princeton subject headings:
Aljustrel (Beja, Portugal)--Social conditions.
Mineral industries--Portugal--Aljustrel (Beja)--History.
Miners--Labor unions--Portugal--Aljustrel--History.
Miners--Portugal--Aljustrel (Beja)--Social conditions.