American Association of State Highway and Transportation Officials (1989). United States Numbered Highways (1989 ed.). Washington, DC: American Association of State Highway and Transportation Officials. OCLC37586174. Archived from the original on February 4, 2007.
American Association of State Highway and Transportation Officials. "Committee Action Reports". American Association of State Highway and Transportation Officials. Archived from the original on February 3, 2007. Retrieved August 16, 2007.
American Association of State Highway and Transportation Officials (1989). United States Numbered Highways (1989 ed.). Washington, DC: American Association of State Highway and Transportation Officials. OCLC37586174. Archived from the original on February 4, 2007.
American Association of State Highway and Transportation Officials. "Committee Action Reports". American Association of State Highway and Transportation Officials. Archived from the original on February 3, 2007. Retrieved August 16, 2007.
American Association of State Highway and Transportation Officials (1989). United States Numbered Highways (1989 ed.). Washington, DC: American Association of State Highway and Transportation Officials. OCLC37586174. Archived from the original on February 4, 2007.