This primary source comes from the Records of the Office of the Chief Signal Officer.
National Archives Identifier:
530734Full Citation: American troops on way to the front march thru London amid the plaudits of the multitudes, crossing Westminster Bridge.; 9/5/1917; Records of the Office of the Chief Signal Officer, Record Group 111. [Online Version, https://docsteach.org/documents/document/american-troops-on-way-to-the-front-march-thru-london-amid-the-plaudits-of-the-multitudes-crossing-westminster-bridge, May 11, 2024]