428-GX-K-121166:   An aerial view of the U.S. Naval Observatory Grounds, April 1977.  U.S. Navy Photograph now in the collections of the National Archives. Photographed from reference card only.   (2016/01/19).
<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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