Parallel Problem Solving from Nature - PPSN IX 9th International Conference, Reykjavik, Iceland, September 9-13, 2006, Proceedings - Runarsson, Thomas Philip; Beyer, Hans-Georg; Burke, Edmund; Merelo-Guervós, Juan J.; Whitley, L. Darrell; Yao, Xin (Springer Berlin Heidelberg, 2006)