Viktor Zykov Josh C. Bongard Hod Lipson Co-evolutionary Variance Can Guide Physical Testing in Evolutionary System Identification. 213-220 2005 conf/eh/2005 Evolvable Hardware http://doi.ieeecomputersociety.org/10.1109/EH.2005.13 db/conf/eh/eh2005.html#ZykovBL05