@inproceedings{derspherical06,
  title = {Let It Roll -- Emerging Sensorimotor Coordination in a Spherical Robot},
  booktitle = {Proc,\ Artificial Life X},
  pages = {192--198},
  publisher = {Intl.~Society for Artificial Life, MIT Press},
  month = aug,
  year = {2006},
  author = {Der, Ralf and Martius, Georg and Hesse, Frank},
  month_numeric = {8}
}