Columbia subject headings:
Bebel, August, 1840-1913.
Kautsky, Karl, 1854-1938.
Socialism--Germany--History.
Harvard subject headings:
Bebel, August, 1840-1913
Kautsky, Karl, 1854-1938.
Socialism--Germany
Socialism--Germany--History
Princeton subject headings:
Bebel, August, 1840-1913.
Kautsky, Karl, 1854-1938.
Socialism--Germany--History.