A. Sarafopoulos. Genetic Programming, Proceedings of EuroGP'2001, volume 2038 of LNCS, page 176--191. Lake Como, Italy, Springer-Verlag, (18-20 April 2001)
R. Aler, D. Borrajo, and P. Isasi. Proceedings of the 2001 Congress on Evolutionary
Computation CEC2001, page 1220--1227. COEX, World Trade Center, 159 Samseong-dong,
Gangnam-gu, Seoul, Korea, IEEE Press, (27-30 May 2001)