This primary source comes from the Records of the Office of the Chief Signal Officer.
National Archives Identifier:
530722Full Citation: French soldiers making a gas and flame attack on German trenches in Flanders. Belgium; Records of the Office of the Chief Signal Officer, Record Group 111. [Online Version, https://docsteach.org/documents/document/french-soldiers-making-a-gas-and-flame-attack-on-german-trenches-in-flanders-belgium, April 23, 2024]