Title: The Moscow Puzzles: 359 Mathematical Recreations, Author: Boris A. Kordemsky
Title: Guesstimation: Solving the World's Problems on the Back of a Cocktail Napkin, Author: Lawrence Weinstein
Title: Riddles in Mathematics: A Book of Paradoxes, Author: Eugene P Northrop
Title: The Mathematical Recreations of Lewis Carroll: Pillow Problems and a Tangled Tale, Author: Lewis Carroll
Title: Professor Stewart's Hoard of Mathematical Treasures, Author: Ian Stewart