- Department of the Navy. Office of the Chief of Naval Operations. Office of the Deputy Chief of Naval Operations (Operations). Naval Intelligence Division. Office of Naval Records and Library. (8/1/1946 - 9/18/1947)
- National Archives at Washington, DC - Textual Reference
This is the diary of German Lieutenant Walter Schwieger and his account of the sinking of the Lusitania in 1915.
- War diaries