[Dunninger, Joseph] Arthur Conan Doyle?s Son Challenges Dunninger?s Expos? in Life Magazine. A four-page typed letter signed, dated June 20, 1941, from Denis P.S. Conan Doyle, Arthur Conan Doyle?s son, to the editors of Life, defending genuine mediums as ?invaluable member[s] of the world community,? and refuting claims in an article by Dunninger in Life that Conan Doyle?s father, Arthur, had given Dunninger a ?code message? before his death: ?My father never left a code or secret message with anyone in the world, not even with any member of his own family?? Signed ?Denis P.S. Conan Doyle.? With a cover letter from Life, forwarding the letter to Dunninger.