Advances in Learning Classifier Systems 4th International Workshop, IWLCS 2001, San Francisco, CA, USA, July 7-8, 2001. Revised Papers - Lanzi, Pier L.; Lanzi, Pier L.; Stolzmann, Wolfgang; Stolzmann, Wolfgang; Wilson, Stewart W.; Wilson, Stewart W. (Springer Berlin Heidelberg : Imprint: Springer, 2002)