Columbia subject headings:
Political violence--Spain--History.
Spain--History--Civil War, 1936-1939.
Harvard subject headings:
Political persecution--Spain--History--20th century
Political violence--Spain--History--20th century.
Spain--History--Civil War, 1936-1939--Atrocities
Princeton subject headings:
Political violence--Spain--History.
Spain--History--Civil War, 1936-1939.