The concept of switching a face-up packet for a group of other face-up cards that are hidden beneath the top face-down card of the deck, appeared in Jean Hugard and Fred Braue's Miracle Methods No. 1: The Stripper Deck, 1941, p. 25 and p. 31. This used the stripped feature of the cards to aid in the switching action.
Ed Marlo brought the idea to a regular pack of cards with his “convincing addition move” in Ten Hand Poker Stack, 1974, p. 164. Harvey Rosenthal refined Marlo's handling shortly after. Alex Elmsley, working independently in England, also developed a handling, which he recorded in his personal notes but never published. Rosenthal showed his handling to Ken Krenzel, who proceeded to come up with another handling, which he called the “slide under switch” and published in Epilogue Special, No. 2, n.d. (c. 1974), p. 246. Another handling was published by Darwin Ortiz in Cardshark, 1995, p. 161. Rosenthal has not yet published the details of his version.