Interstate Highway System
Hearings Before the Committee on Post Offices and Post Roads, United States Senate, Sixty-seventh Congress, First Session, on S. 1355 a Bill to Provide for the Establishment, Construction, and Maintenance of a Post Roads and Interstate Highway System, to Create a Federal Highway Commission, and for Other Purposes, May 13, 23, 24, 25, 26, 27, 28; June 1, 2, 1921