Bureau of Air Commerce (U.S. Department of Commerce) report into the accident investigation of the crash of a Wyoming Air Service flight on 27 May 1935
Civil Aeronautics Bureau
1935-10-03
National Transportation Library, U.S. Department of Transportation. <a rel="nofollow" class="external free" href="https://rosap.ntl.bts.gov/view/dot/32936">https://rosap.ntl.bts.gov/view/dot/32936</a>