Path planning by optimal-path-map construction for homogeneous-cost two-dimensional regions. - Robert S. Alexander; Neil C. Rowe (ICRA, 1990)

Finding Optimal-Path Maps for Path Planning across Weighted Regions. - Neil C. Rowe; Robert S. Alexander (Int. J. Robotics Res., 2000)

A multi threaded and resolution approach to simulated futures evaluation. - David R. Pratt; Robert W. Franceschini; Robert B. Burch; Robert S. Alexander (WSC, 2008)