Columbia subject headings:
Ireland--Politics and government--19th century.
Ireland--Politics and government--20th century.
Irish question--History.
Harvard subject headings:
Ireland--Politics and government--19th century.
Ireland--Politics and government--20th century.
Northern Ireland--Politics and government--1968-1998.
Princeton subject headings:
Ireland--Politics and government--19th century.
Ireland--Politics and government--20th century.
Irish question--History.