1. [1] M. Vukobratovic and J. Stepanenko, On the Stability of Anthropomorphic Systems, Mathematical Biosciences, Vol. 15, pp. 1-37, 1972.
2. [4] T. McGeer, Passive Dynamic Walking, The Int. J. of Robotics Research, Vol. 9, No. 2, pp. 62-82, 1990.
3. [5] T. McGeer, Principles of Walking and Running, Advances in Comparative and Environmental Physiology, Springer-Verlag, 1991.
4. [6] T. McGeer, Passive Walking with Knees, Proc. of the 1990 IEEE Int. Conf. on Robotics and Automation, pp. 1640-1645, 1990.
5. [7] A. Goswami, B. Thuilot and B. Espiau, A Study of the Passive Gait of a Compass-Like Biped Robot: Symmetry and Chaos, The Int. J. of Robotics Research, Vol. 17, No. 12, pp. 1282-1301, 1998.