Columbia subject headings:
Labor supply--Peru.
Mineral industries--Peru--History--19th century.
Peru--Economic conditions.
Harvard subject headings:
Labor market--Peru--Sierra.
Miners--Supply and demand--Peru--Sierra.
Peasants--Peru--Sierra.
Princeton subject headings:
Miners--Peru--Cerro de Pasco--History--19th century.
Peru--Economic conditions.
Silver mines and mining--Peru--Cerro de Pasco--Economic aspects.