National Research Council (U.S.). Transportation Research Board & National Research Council (U.S.). Transportation Research Board. Meeting. (2004). Traffic control devices, visibility, and rail-highway grade crossings, 2004. National Academy Press.
Chicago-referens (17:e uppl.)National Research Council (U.S.). Transportation Research Board och National Research Council (U.S.). Transportation Research Board. Meeting. Traffic Control Devices, Visibility, and Rail-highway Grade Crossings, 2004. Washington, D.C: National Academy Press, 2004.
MLA-referens (9:e uppl.)National Research Council (U.S.). Transportation Research Board och National Research Council (U.S.). Transportation Research Board. Meeting. Traffic Control Devices, Visibility, and Rail-highway Grade Crossings, 2004. National Academy Press, 2004.