Short stories by Agatha Christie have been published in many collections, lots of them duplicating each other. For example, The Harlequin Tea Set contains almost all the same stories as While the Light Lasts. But a little sorting out has revealed...
Here from philosopher/logician/puzzlemaker Raymond Smullyan are fifty elegant, witty, and altogether unique "chess mysteries." In each problem the solver has to deduce certain events in a game's past. For example: On what square was...