This primary source comes from the Records of the Office of the Chief Signal Officer.
National Archives Identifier:
528037Full Citation: Walt Whitman; ca. 1860 - 1865; Mathew Brady Photographs of Civil War-Era Personalities and Scenes, 1921 - 1940; Records of the Office of the Chief Signal Officer, Record Group 111; National Archives at College Park, College Park, MD. [Online Version, https://docsteach.org/documents/document/walt-whitman-white-shirt, April 22, 2025]