Public Roads;Federal Highway Administrationhttps://doi.org/10.21949/15237141940PDFJournalNormann, O. K.Barker, F. N.Palmer, L. A.United States. Federal Works Agency. Public Roads Administration{65772}United States. Government Printing Office{1103}United StatesPublic roadsStudiesInfrastructureResearchStatisticsHIGHWAY STATISTICSVolume 20, Issue(s) 12These documents are disseminated under the sponsorship of the U.S. Department of Transportation, Federal Highway Administration, in the interest of information exchange.The U.S. Department of Transportation does not endorse any manufacturers, products, or services cited herein and any business or trade names that may appear in these documents have been included only as necessary to further the pu...