Columbia subject headings:
Existentialism.
Lavelle, Louis.
Sartre, Jean-Paul, 1905-1980.
Harvard subject headings:
Existentialism.
Lavelle, Louis, 1883-1951.
Sartre, Jean-Paul, 1905-1980
Princeton subject headings:
Lavelle, Louis, 1883-1951.
Sartre, Jean-Paul, 1905-1980.