J. Rose, Y. Gao, M. Garzon, und R. Murphy. Genetic Programming 1997: Proceedings of the Second
Annual Conference, Seite 479--490. Stanford University, CA, USA, Morgan Kaufmann, (13-16 July 1997)
L. Rovcanin, und J. Murphy. ADBIS (Short Papers), Seite 214-220. Institute of Informatics, Faculty of Electrical Engineering and Computer Science, Smetanova 17, IS-2000 Maribor, Slovenia, (1999)