1. Cramer, N.L.: A representation for the adaptive generation of simple sequential programs. In: Grefenstette, J.J. (ed.) Proceedings of the First International Conference on Genetic Algorithms and their Applications, Hillsdale, NJ, Carnegie-Mellon University, pp. 183–187. Lawrence Erlbaum Associates, Mahwah (1985)
2. Koza, J.R.: Genetic Programming. The MIT Press, Cambridge (1992)
3. Angeline, P.J., Pollack, J.B.: The evolutionary induction of subroutines. In: Proceedings of the Fourteenth Annual Conference of the Cognitive Science Society, Hillsdale, NJ, pp. 236–241. Lawrence Erlbaum Associates, Mahwah (1992)
4. Koza, J.R.: Genetic Programming II: Automatic Discovery of Reusable Programs. The MIT Press, Cambridge (1994)
5. Rosca, J.P., Ballard, D.H.: Discovery of subroutines in genetic programming. In: Angeline, P., Kinnear Jr., K.E. (eds.) Advances in Genetic Programming 2, pp. 177–202. The MIT Press, Cambridge (1996)