2007, Article / Letter to editor (Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics, vol. 76, iss. 1 Pt 1, (2007), pp. 011102-1-011102)
2000, Part of book or chapter of book (Ritter, H.; Cruse, H.; Dean, J. (ed.), Prerational Intelligence: Adaptive Behavior and Intelligent Systems Without Symbols and Logic, pp. 157-164)
1999, Article in monograph or in proceedings (ICANN 99 : Ninth International Conference on Artificial Neural Networks, University of Edinburgh, 7-10 september, 1999, pp. 425-431)
1997, Part of book or chapter of book (Kappen, B. (ed.), Neural Networks: Best Practice in Europe : Proceedings of the Stichting Neurale Netwerken Conference 1997 (Progress in Neural Processing), pp. 128-135)