"Julien Keller’ was the nom de guerre of Adolfo Kaminsky, who died in Paris last month aged 97. It was largely thanks to him that the German-occupied zone of wartime France was flooded with false documents. The Occupation authorities were on his trail, but they never suspected that the forger they were after was a teenager."

https://www.lrb.co.uk/the-paper/v45/n04/adam-shatz/beyond-borders