Columbia subject headings:
Spain--History--Civil War, 1936-1939--Causes.
Spain--Politics and government--1931-1939.
Harvard subject headings:
Spain--History--Civil War, 1936-1939--Causes.
Spain--Politics and government--1931-1939.
Princeton subject headings:
Spain--History--Civil War, 1936-1939--Causes.
Spain--Politics and government--1931-1939.