1. Federal Railroad Administration (FRA), Trains Blocking Highway-Rail Grade Crossing Fact Sheet, Office of Public Affairs, US Department of Transportation, May 2008
2. Texas Constitution and Statutes, Transportation Code, Title 6: Roadways, Subtitle Z: Miscellaneous Roadway Provisions, Railroad and Roadway Crossings, September 1999 (Chapter 471).
3. Nebraska Department of Road (NDOR), Title 415: Comprehensive Public Safety Program for Highway-Rail Grade Crossings, NE Code 74-1342, Nebraska Rail and Public Transportation Division, 2013 (Chapter 7).
4. Transport Canada, Canadian Rail Operating Rules, TC O 0-167, December 2013.
5. Transport Canada, Stronger Ties: A Shared Commitment to Railway Safety-Review of the Railway Safety Act, Railway Safety Act Review Secretariat, Ottawa, Canada, ISBN: 978-0-662-05408-5, November, 2007.