A McDonnell XH-20 <i>Little Henry</i> in flight.
U.S. Navy
<a rel="nofollow" class="external text" href="http://www.navy.mil/ah_online/department_arch.html">U.S. Navy All Hands magazine</a> <a rel="nofollow" class="external text" href="http://www.navy.mil/ah_online/archpdf/ah194905.pdf">May 1949</a>, p. 40.