Columbia subject headings:
Marx, Karl, 1818-1883.
Reich, Wilhelm, 1897-1957.
Social classes.
Socialism.
Harvard subject headings:
Marx, Karl, 1818-1883
Reich, Wilhelm, 1897-1957
Social classes.
Socialism.
Princeton subject headings:
Marx, Karl, 1818-1883.
Reich, Wilhelm, 1897-1957.
Social classes.
Socialism.