80-G-416207:  O2C-4’s in formation with monument in the background at Washington, D.C., June 3, 1933.   Official U.S. Navy Photograph, now in the collections of the National Archives.  (2016/10/18).
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/127906254@N06">National Museum of the U.S. Navy</a>
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