Columbia subject headings:
Coal mines and mining--Russia (Federation)--History--19th century.
Iron industry and trade--Russia (Federation)--History--19th century.
Harvard subject headings:
Coal mines and mining--Russia (Federation)--History--19th century.
Coal mines and mining--Russia--History--19th century.
Iron industry and trade--Russia (Federation)--History--19th century.
Iron industry and trade--Russia--History--19th century.
Princeton subject headings:
Iron industry and trade--Soviet Union--History.
Mines and mineral resources--Soviet Union--History.
Steel industry and trade--Soviet Union--History.