Columbia subject headings:
Austria--Economic conditions--19th century.
Customs unions--History--19th century.
Hungary--Economic conditions--19th century.
Harvard subject headings:
Austria--Economic conditions--19th century
Customs unions--History--19th century.
Hungary--Economic conditions--19th century
Princeton subject headings:
Austria--Economic conditions--19th century.
Customs unions--History--19th century.
Hungary--Economic conditions--19th century.