Office of the Chief of Naval Operations to All United States Naval Forces
<Cablegram, May 21, 1918.>
SEVENTY-EIGHT ALNAV May – 1918.
Commanders of All Naval Vessels shall comma whenever possible comma, take necessary steps to assure themselves of the character of all vessels sighted on the high seas in accordance with International Laws and Usage. 23021
Source Note: Cy, DNA, RG 45, Entry 517B.