C. de Duve (1995) Vital Dust: Life as a cosmic imperative. Basic Books, NY 362pp
Baltschefsky, H et al (1997) Special issue J. theor. Biol. 187:453-629 Aug. 1997
Maynard Smith, J. and Sathmary, E. (1995) The major transitions in
evolution. Freeman-Spektrum, Oxford 345 pp