(1978). Manual on uniform traffic control devices for streets and highways. Washington, D C: U S Department of Transportation.
Chicago-referens (17:e uppl.)Manual on Uniform Traffic Control Devices for Streets and Highways. Washington, D C: U S Department of Transportation, 1978.
MLA-referens (9:e uppl.)Manual on Uniform Traffic Control Devices for Streets and Highways. Washington, D C: U S Department of Transportation, 1978.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.