Civil Aeronautics Board report into the mid-air collision of a Civil Air Patrol Aeronica L-16A and a Cessna 140 on 30 September 1959.
Civil Aeronautics Board, US Department of Commerce
1961-05-17
US Department of Transportation Special Collection <a rel="nofollow" class="external autonumber" href="http://specialcollection.dotlibrary.dot.gov/Contents">[1]</a>