[1] [M. Raibert, "Legged Robots that Balance"], 1986, MIT Press, ISBN 0-262-18117-7.

[2] [M. Raibert, M. and J. Hodgins, "Animation of Dynamic Legged Locomotion"] Computer Graphics, Vol. 25, #4, July 1991.

[3] [J. Nagle, "Realistic Animation of Legged Running on Rough Terrain"] in Proc. 1995 IEEE Computer Animation Conference, Geneva.