56th Field Artillery Command distinctive unit insignia
U.S. Army
1972-04-11<a rel="nofollow" class="external autonumber" href="http://www.tioh.hqda.pentagon.mil/Catalog/HeraldryMulti.aspx?CategoryId=3448&amp;grp=2&amp;menu=Uniformed%20Services">[1]</a>
<cite class="book" style="font-style:normal">McKenney, Janice E. (2010)      <i> <a rel="nofollow" class="external text" href="http://www.history.army.mil/catalog/pubs/60/60-11.html">Field Artillery</a></i> (PDF), Army Lineage Series (Second ed.), <a href="//commons.wikimedia.org/wiki/Category:Washington_D.C." title="Category:Washington D.C.">Washington D.C.</a>:  U.S. Army Center of Military History  <small>CMH Pub 60-11</small></cite>