S. Luke, and L. Spector. Genetic Programming 1998: Proceedings of the Third
Annual Conference, page 208--213. University of Wisconsin, Madison, Wisconsin, USA, Morgan Kaufmann, (22-25 July 1998)
J. Klein, and L. Spector. GECCO '07: Proceedings of the 9th annual conference on
Genetic and evolutionary computation, 2, page 1628--1635. London, ACM Press, (7-11 July 2007)
R. Crawford-Marks, L. Spector, and J. Klein. Late Breaking Papers at the 2004 Genetic and
Evolutionary Computation Conference, Seattle, Washington, USA, (26 July 2004)