Columbia subject headings:
Harvard subject headings:
Europe--History--1789-1900.
Europe--History--20th century.
Europe--Politics and government--1789-1900.
Europe--Politics and government--20th century.
Princeton subject headings:
Europe--History--1789-1900.
Europe--History--20th century.
Europe--Politics and government--1789-1900.
Europe--Politics and government--20th century.