I'm looking for an opening I saw in a book (not a chess book). The opening was about 10 moves long, and the author stated that the evaluation after the last move shown had been considered for many years in many chess books as "black has a slight advantage", but later it had been shown that white could checkmate in 1 move.
Additional information: the book I read was written by Martin Gardner. It was not a chess book, but possibly a collection of his Scientific American columns, published in the 60s - 80s. This chess opening was (if I remember correctly) an example in a chapter devoted to puzzles and problems, unrelated to chess, that had been published with a wrong solution, or with a solution that later had been improved.