Henry Christ's force using a double-backed card, which Theodore Annemann named “The 203rd Force”, was first published in Annemann's Sh-h-h--! It's a Secret, 1934, p. 41.
Christ applied the same procedure to a location of a card freely cut to. This was first published in Hugard and Braue's Miracle Methods, No. 3: Prepared Cards and Accessories, 1942, p. 8.
Christ's procedure led to a number of variations and refinements. Among the more interesting are these: George Kaplan corner-shorted the double-backed card, making it faster to locate and glimpse the selection above it; see Kaplan's Fine Art of Magic, 1948, p. 44. Paul Curry clipped off more, making the double-backer a short card, which added the facilitation of a Double Lift in his “Turn of the Century” in Paul Curry Presents, 1974, p. 57.