Krister Wolff Peter Nordin Learning Biped Locomotion from First Principles on a Simulated Humanoid Robot Using Linear Genetic Programming. 495-506 2003 conf/gecco/2003-1 GECCO http://link.springer.de/link/service/series/0558/bibs/2723/27230495.htm db/conf/gecco/gecco2003-1.html#WolffN03