Columbia subject headings:
Harvard subject headings:
Spain--Foreign relations--1931-1939.
Spain--History--Civil War, 1936-1939--Participation, Foreign.
Spain--History--Civil War, 1936-1939.
Princeton subject headings:
Spain--Foreign relations--1931-1939.
Spain--History--Civil War, 1936-1939--Participation, Foreign.
Spain--History--Civil War, 1936-1939.