Columbia subject headings:
Communism--Bibliography.
Engels, Friedrich, 1820-1895--Bibliography.
Marx, Karl, 1818-1883--Bibliography.
Socialism--Bibliography.
Harvard subject headings:
Communism--Bibliography
Engels, Friedrich, 1820-1895--Bibliography.
Marx, Karl, 1818-1883--Bibliography.
Socialism--Bibliography
Princeton subject headings:
Communism--Italy--Bibliography.
Engels, Friedrich, 1820-1895.
Marx, Karl, 1818-1883.
Socialism--Italy--Bibliography.