1. C. Borgelt, M. Steinbrecher, R. Kruse, Graphical Models: Representations for Learning, Reasoning and Data Mining, 2nd edn. (Wiley, Chichester, United Kingdom, 2009)
2. M. Dorigo, T. Stützle, Ant Colony Optimization (MIT Press, Cambridge, MA, USA, 2004)
3. S.O. Haykin, Neural Networks and Learning Machines, 3rd edn. (Prentice Hall, Upper Saddle River, NJ, USA, 2008)
4. E. Hüllermeier, R. Kruse, F. Hoffmann (eds.), Computational Intelligence for Knowledge-Based Systems Design (Springer, Berlin/Heidelberg, Germany, 2010)
5. J. Kacprzyk, W. Pedrycz (eds.), Springer Handbook of Computational Intelligence (Springer, Berlin/Heidelberg, Germany, 2015)