(PDF)于2012-09-07). The National Forests of the UnitedStates (PDF). ForestHistory.org. [2012-07-30]. (原始内容 (PDF)存档于2013-02-12). Staff. Utah Forest Highway Long Range
Development of UnitedStates Numbered HighwaysPDF (15.6 KiB), revised October 6, 1996 What Is The Longest Road in the UnitedStates?. Federal Highway Administration