Columbia subject headings:
Lopatin, German Aleksandrovich, 1845-1918.
Marx, Karl, 1818-1883.
Socialism--History.
Harvard subject headings:
Lopatin, German Aleksandrovich, 1845-1918.
Marx, Karl, 1818-1883
Socialism--History
Princeton subject headings:
Lopatin, German Aleksandrovich, 1845-1918.
Marx, Karl, 1818-1883.
Socialism--History.