Dr. Gareth Moore 
Think Outside the Box [PDF ebook] 

Are you ready to bend your mind and think in new ways? Pit your wits against these super-cool puzzles and see where they take you! Use your eyes and memory to… ? find your way through mazes ? solve 3D puzzles ? turn a circle into a square …and lots more. Devised by an expert on brain training, these mental challenges will fire up your powers of imagination and logic. There are handy tips if you need help, plus an answer key at the back!