I. Ma, T. Wong, und T. Sankar. GECCO '07: Proceedings of the 9th annual conference on
Genetic and evolutionary computation, 2, Seite 2262--2262. London, ACM Press, (7-11 July 2007)
Y. Becker, P. Fei, und A. Lester. Genetic Programming Theory and Practice IV, Volume 5 von Genetic and Evolutionary Computation, Kapitel 12, Springer, Ann Arbor, (11-13 May 2006)