1. Burnham, A. Stop sign effectiveness at railroad grade crossings: abuse without excuse. Proceedings of the Third International Symposium on Railroad–Highway Grade Crossing Research and Safety. pp.41–49. Knoxville, TN: University of Tennessee.
2. Federal Railroad Administration. 2008. Available at:http://safetydata.fra.dot.gov/officeofsafety/Home page (accessed July 19, 2008)
3. Induced exposure