Columbia subject headings:
Harvard subject headings:
China--Commerce--United States--History--18th century.
China--Commerce--United States--History--19th century.
United States--Commerce--China--History--18th century.
United States--Commerce--China--History--19th century.
Princeton subject headings:
China--Commerce--United States--History--19th century.
United States--Commerce--China--History--19th century.