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Jean Hugard published his “Enveloped” in Hugard's Magic Monthly, Vol. 14 No. 4, Sep. 1956, p. 469. It is also mentioned in Robert Parrish and Bert Allerton's The Close-up Magician, 1958, p. 66. Also related is Sid Lorraine's “Prediction” in The Jinx, No. 65, Nov. 4 1939, p. 456.