Columbia subject headings:
Harvard subject headings:
Labor unions--Germany--Political activity--History--20th century.
Schuck, Julius, 1897-1958.
Socialism--Germany--History--20th century
Socialists--Germany--Biography
Princeton subject headings:
Labor unions--Germany--Political activity--History--20th century.
Schuck, Julius, 1897-1958.
Socialism--Germany--History--20th century.
Socialists--Germany--Biography.