Seeking list of French Medal of Honor given to American Ambulance Drivers

Seeking records WWI French Medal of Honor to American Ambulance Drivers. The Croix de Guerre 1914–1918 is a French military decoration, the first version of the Croix de Guerre. How would I find records of my Grand-father who was an Ambulance Driver that saved several French soldiers, receiving this medal in France. The French Croix de Guerre was awarded to French and Allied soldiers, including 11,589 Americans, for their service during World War I and was authorized by French legislation on April 2, 1915.  Are there documents that list these Americans?

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