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An American gun crew from Regimental Headquarters Company, 23rd Infantry, fires a 37mm gun during an advance against German entrenched positions.
Credit: Reuters
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An American Expeditionary Force doctor tends to an injured American soldier immediately behind the first trench line in France, in 1919.
Credit: Reuters
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U.S. soldiers of the American Expeditionary Force are seen during a pause in fighting.
Credit: Reuters
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American soldiers keep watch in a trench in France.
Credit: Reuters
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American soldiers react to a gas attack in an undated photo, likely used for training purposes.
Credit: Reuters