Best of Friends Volume I by Harry Lorayne Page 285 et seq.
Personal Comment: The little trick lacks logic. Yet the climax is strangly fullfilling. Try it, it is quick and a nice filler inbetween longer pieces. The cards in use remind of a sandwich routine therefore it seems right to do one before or after the trick. It is hard to compare the effect with the usual stuff, so it becomes a nice interlude. I like it.