Columbia subject headings:
Spain--History--Republic, 1931-1939.
Spain--Politics and government--1931-1939.
Harvard subject headings:
Radicalism--Spain--20th century.
Spain--History--Republic, 1931-1939
Spain--Politics and government--1931-1939
Princeton subject headings:
Radicalism--Spain--20th century.
Spain--Politics and government--1931-1939.