Genetic Programming 6th European Conference, EuroGP 2003, Essex, UK, April 14-16, 2003. Proceedings - Ryan, Conor; Ryan, Conor; Soule, Terence; Soule, Terence; Poli, Riccardo; Poli, Riccardo; Tsang, Edward; Tsang, Edward; Keijzer, Maarten; Keijzer, Maarten; Costa, Ernesto; Costa, Ernesto (Springer Berlin Heidelberg : Imprint: Springer, 2003)