Columbia subject headings:
Chile--Commerce--History.
Chile--Economic conditions.
Chile--Economic policy.
Fertilizer industry--Chile--History.
Nitrates--History.
Harvard subject headings:
Chile--Commerce--History.
Chile--Economic conditions.
Chile--Economic policy.
Fertilizer industry--Chile--History.
Nitrates--History.
Princeton subject headings:
Chile--Commerce--History.
Chile--Economic conditions.
Chile--Economic policy.
Fertilizer industry--Chile--History.
Nitrates--History.