This article is based on
[1] L. Kavraki, J.-C. Latombe. Probabilistic Roadmaps for Robot Path Planning. (chapter 3 in the book "Gupta et al. Practical Motion Planning in Robotics. ISBN 0-471-98163-X)
[2] S. Wilmarth, N. Amato, P. Stiller. Motion Planning for a Rigid Body Using Random Networks on the Medial Axis of the Free Space. Proceedings of the 15th Annual ACM Symposium on Computational Geometry, 1999, pp. 173-180