Columbia subject headings:
Brazil, Northeast--Economic conditions.
Brazil, Northeast--History.
Brazil--History--Empire, 1822-1889.
Harvard subject headings:
Brazil, Northeast--Economic conditions.
Brazil, Northeast--History.
Brazil--Foreign relations--1930-1945.
Brazil--History--Empire, 1822-1889.
Princeton subject headings:
Brazil, Northeast--Economic conditions.
Brazil, Northeast--History.
Brazil--History--Empire, 1822-1889.