1. United States system of numbered highways adopted for uniform marking by American Association of State Highway Officials, together with Federal Aid Highway System, approved in accordance with act of Nov. 9, 1921, and subsequent amendments thereto, [map]; corrected to Jan. 1, 1950. Scale 37 m.=1 in. Bookmark Corporate/Agency Authors: Public Roads Bureau and Commerce Dept. Publisher: Public Roads Bureau Date: [1951.] SuDoc number: C 37.13:H 53/950/Sh.1,2