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In Mark Sicher and Steve Cohen's “Quart(er)z Watch” from Apocalypse, Vol. 13 No. 4, Apr. 1990, p. 1765, the idea of loading a coin under a spectator's watch is credited to Gazzo Macée (Gary Osborne). The Sicher-Cohen trick may be the first publication of the idea.
See also Card under Wristwatch.