1. Axelrod, R.M. 1984. The evolution of cooperation. New York: Basic Books.
2. Clark, C.W. 1976. Mathematical bioeconomics: The optimal management of renewable resources. New York: Wiley–Interscience.
3. Darwin, C. 1859. On the origin of species by means of natural selection, or, the preservation of favoured races in the struggle for life. London: John Murray.
4. Dawkins, R. 1976. The selfish gene. Oxford: Oxford University Press.
5. Krebs, J.R., and N.B. Davies. 1984. Behavioural ecology: An evolutionary approach, 2nd ed. Oxford: Blackwell.