Columbia subject headings:
Communist ethics.
Engels, Friedrich, 1820-1895--Criticism and interpretation.
Marx, Karl, 1818-1883--Criticism and interpretation.
Harvard subject headings:
Engels, Friedrich, 1820-1895--Ethics.
Marx, Karl, 1818-1883--Ethics.
Princeton subject headings:
Communist ethics.
Engels, Friedrich, 1820-1895--Ethics.
Marx, Karl, 1818-1883--Ethics.