Amazon.com: Fun Puzzle Balls with Free Colorful Instruction Guide by Gamie - Party Games - Fidget Brain Teaser Puzzles - Includes 12 Fun and Challenging Puzzle Balls - Great Educational Toy for
The Cube: The Ultimate Guide to the World's Bestselling Puzzle - Secrets, Stories, Solutions: Jerry Slocum, David Singmaster, Wei-Hwa Huang, Dieter Gebhardt, Geert Hellings, Erno Rubik: 9781579128050: Amazon.com: Books