Download or read book Sudoku Puzzle Book, 500 Extra Hard Puzzles written by Sudoku Books and published by Createspace Independent Publishing Platform. This book was released on 2017-01-18 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: Relieve boredom and stress by playing Sudoku. This big book contains plenty of puzzles to keep you busy for many hours. There are 4 puzzles per page and solutions are at the end of the book.