D. Howard, S. Roberts, и R. Brankin. Late Breaking Papers at the Genetic Programming 1998
Conference, University of Wisconsin, Madison, Wisconsin, USA, Stanford University Bookstore, (22-25 July 1998)
D. Howard, S. Roberts, и R. Brankin. Genetic Programming, Proceedings of EuroGP'99, том 1598 из LNCS, стр. 135--148. Goteborg, Sweden, Springer-Verlag, (26-27 May 1999)