Gould,Stephen Jay. Wonderful Life: The Burgess Shale and the Nature of History
     New York: WW Norton, 1989

Sheldrake, Rupert. The Rebirth of Nature. The Greening of Science and God
      Rochester, VT: Park Street Press, 1994

Shaw, Herbert. Craters, Cosmos, and Chronicles: A New Theory of Earth
      Stanford, CA: Stanford University Press, 1994