File:Map of Naval Districts 1944 Source Furer, Julius Augustus. Administration of the Navy Department in World War II. (Washington, D.C. US Government Printing Office, 1959) 521..gif

Summary
Source: Furer, Julius Augustus. Administration of the Navy Department in World War II. (Washington, D.C.: US Government Printing Office, 1959): 521. https://en.wikipedia.org/wiki/Template:PD-URAA