Columbia subject headings:
Abbagnano, Nicola, 1901-1990.
Existentialism.
Marcel, Gabriel, 1889-1973.
Marx, Karl, 1818-1883.
Sartre, Jean-Paul, 1905-1980.
Harvard subject headings:
Abbagnano, Nicola, 1901-1990.
Existentialism.
Marcel, Gabriel, 1889-1973.
Marx, Karl, 1818-1883
Sartre, Jean-Paul, 1905-1980
Princeton subject headings:
Abbagnano, Nicola, 1901-1990.
Existentialism.
Marcel, Gabriel, 1889-1973.
Marx, Karl, 1818-1883.
Sartre, Jean-Paul, 1905-1980.