Columbia subject headings:
Anarchism--Spain--Barcelona--History--20th century.
Barcelona (Spain)--Social conditions--20th century.
Confederación Nacional del Trabajo (Spain)
Labor movement--Spain--Barcelona--History--20th century.
Harvard subject headings:
Anarchism--Spain--Barcelona--History--20th century.
Barcelona (Spain)--Social conditions--20th century.
Confederación Nacional del Trabajo (Spain)
Labor movement--Spain--Barcelona--History--20th century.
Princeton subject headings: