White to play. Mista–Kloza, Poland 1955 (supposedly). Which move does White play to force a quick checkmate? Answers should be emailed to chess@spectator.co.uk by Tuesday 17 November. There is a prize of £20 for the first correct answer out of a hat. Please include a postal address and allow six weeks for prize delivery.

Last week’s solution 1 Kd7! If 1…Bg7 2 Nd6 and 3 Ne8 mate. Or if 1…Kg7, 2 Nd6 and Nd6-e8, Nd6xf5 or Ng5-e6 mate.
Last week’s winner Anca Gramaticu, Oadby, Leicestershire