Columbia subject headings:
Harvard subject headings:
Communists--Spain--Biography
Labor leaders--Spain--Biography.
Maurín, Joaquín, 1897-1973.
Nin, Andrés, 1892-1937.
Socialists--Spain--Biography
Princeton subject headings:
Communists--Spain--Biography.
Maurín, Joaquín, 1897-1973.
Nin, Andrés, 1892-1937.