Columbia subject headings:
Corn laws (Great Britain)
Free trade--Great Britain--History--19th century.
Great Britain--Commerce--History--19th century.
Harvard subject headings:
Corn laws (Great Britain)
Free trade--Great Britain--History--19th century.
Great Britain--Commerce--History--19th century.
Princeton subject headings:
Corn laws (Great Britain)
Free trade--Great Britain--History--19th century.
Great Britain--Commerce--History--19th century.