Analysis of information sources in references of the Wikipedia article "La Grande Illusion" in English language version.
One letter with printed letterhead, the other with punched holes (not touching text). Accompanied by an ALS from Belgian screenwriter Charles Spaak to Renoir in which Spaak accuses the addressee of having cheated him out of the rights of "La Grande illusion", for which Spaak had been a coauthor: "Vieux traitre! ......