Columbia subject headings:
Harvard subject headings:
Communism--Germany--History--20th century
Communists--Germany--Biography
Liebknecht, Karl, 1871-1919
Luxemburg, Rosa, 1871-1919
Princeton subject headings:
Communism--Germany--History--20th century.
Communists--Germany--Biography.
Liebknecht, Karl, 1871-1919.
Luxemburg, Rosa, 1871-1919.