Columbia subject headings:
Harvard subject headings:
Democratization--Spain--History--20th century--Congresses.
Radicalism--Spain--History--20th century--Congresses.
Social movements--Political aspects--Spain--History--20th century--Congresses.
Princeton subject headings:
Left-wing extremists--Spain--History--1975---Congresses.
Radicalism--Spain--History--1975---Congresses.
Social movements--Spain--History--1975---Congresses.
Spain--Politics and government--1975-1982.