This primary source comes from the Records of the War Department General and Special Staffs, 1860 - 1952.
Full Citation: Service flag presented by the Prudential Insurance Company in honor of the men in the service. Newark, New Jersey; 1917 - 1918; Flags - Service Flags; American Unofficial Collection of World War I Photographs, 1917 - 1918; Records of the War Department General and Special Staffs, 1860 - 1952, Record Group 165; National Archives at College Park, College Park, MD. [Online Version, https://www.docsteach.org/documents/document/service-flag-prudential-insurance-newark-nj, May 8, 2024]