Columbia subject headings:
Spain--History--Civil War, 1936-1939--Causes.
Spain--History--Civil War, 1936-1939.
Harvard subject headings:
Civil service--Spain--History--Civil War, 1936-1939.
Spain--Foreign relations--History--Civil War, 1936-1939.
Spain--History--Civil War, 1936-1939--Participation, Foreign.
Princeton subject headings:
Spain--History--Civil War, 1936-1939--Causes.
Spain--History--Civil War, 1936-1939.