Columbia subject headings:
Sudan--History.
Sudan--Politics and government--1956-1985.
Sudan--Politics and government--1985-
Harvard subject headings:
South Sudan--Politics and government.
Sudan--History--Civil War, 1955-1972.
Sudan--Politics and government--1956-1985
Sudan--Politics and government--1985-
Princeton subject headings:
Southern Region (Sudan)--Politics and government.
Sudan--History--Civil War, 1955-1972.
Sudan--Politics and government--1956-1985.
Sudan--Politics and government--1985-