Columbia subject headings:
Andalusia (Spain)--Economic conditions.
Asturias (Spain)--Economic conditions.
Catalonia (Spain)--Economic conditions.
País Vasco (Spain)--Economic conditions.
Harvard subject headings:
Industries--Spain--History--19th century.
Mineral industries--Spain--Andalusia--History--19th century.
Mineral industries--Spain--País Vasco--History--19th century.
Spain--Economic conditions--Regional disparities.
Princeton subject headings:
Andalusia (Spain)--Economic conditions.
Asturias (Spain)--Economic conditions.
Catalonia (Spain)--Economic conditions.
País Vasco (Spain)--Economic conditions.