References

Koestler, Arthur.1967. The Ghost in the Machine. Chicago : Henry Regnery.

Teilhard de Chardin, Pierre.1959. The Phenomenon of Man. London : Wm. Collins Sons.

Teilhard de Chardin, Pierre.1964. The Future of Man. New York : Harper and Row.

Tillich, Paul.1963. “Life and the Spirit  . Systematic Theology, Vol. 3, Part IV. Chicago: Univ. of Chicago Press.