McGrath, W. R. Highway safety program standards. Traffic engineering : official publication of the Institute of Transportation Engineers.
Chicago-referens (17:e uppl.)McGrath, William R. "Highway Safety Program Standards." Traffic Engineering : Official Publication of the Institute of Transportation Engineers .
MLA-referens (9:e uppl.)McGrath, William R. "Highway Safety Program Standards." Traffic Engineering : Official Publication of the Institute of Transportation Engineers, .
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