"A policy on geometric design of highways and streets" Chapter 3 Design elements, 2004, AASHTO
 Mannering F.L., Kilareski W.P., and Washburn S. S, "Principles of Highway Engineering and Traffic Analysis ", 3rd edition, John Wiley & Sons, Inc. 2005
 Ames A.L., Nadeau D.R., and Moreland J.L., "VRML 2.0 Source Book ", 2nd edition, John Wiley & Sons, Inc. 1997
 Online users manual of roadway geometry design software ( PDF).
 CE3201 "Introduction to Transportation Engineering" class notes, Department of Civil Engineering, University of Minnesota, http://www.ce.umn.edu/.