T. Paul, Y. Hasegawa, and H. Iba. Proceedings of the 2006 IEEE Congress on Evolutionary Computation, page 2521--2528. Vancouver, BC, Canada, IEEE Computational Intelligence Society, IEEE Press, (16-21 July 2006)
S. Rouwhorst, and A. Engelbrecht. Proceedings of the 2000 Congress on Evolutionary
Computation CEC00, 1, page 633--638. La Jolla Marriott Hotel La Jolla, California, USA, IEEE Press, (6-9 July 2000)