Photograph showing camouflaged French 340-mm railway gun firing. This gun was operated by American personnel.
Unknown author<span style="display: none;">Unknown author</span>
<p>Railway Artillery: A Report on the Characteristics, Scope of Utility, Etc., of Railway Artillery, Volume I, page 606 by Harry W Miller, United States Army Ordnance Department. Washington, Government Print Office, 1921.
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