More Extreme Sudoku: 200 more of the toughest Sudoku puzzles known to man. (With their solutions.)

"More Extreme Sudoku" is the second volume in the "Extreme Sudoku" series of Sudoku puzzle books acclaimed for their especially challenging puzzles. In creating this second book, Antoine Alary, the mathematician turned engineer, made every effort not to disappoint the fans of his first book, a very select group of Sudoku connoisseurs who have come to expect nothing less than the most challenging 17-clues Sudoku puzzles. The difficulty level of the puzzles in Mr. Alary's books is generally considered to be a good notch or two above the hardest puzzles found in any other book. This book, like its predecessor, contains a selection of 200 of the toughest Sudoku puzzles along with their solutions. These puzzles were selected among 17-clues Sudoku puzzles for their especially challenging nature and will provide hours of enjoyment and ample opportunity to practice the most advanced Sudoku resolution techniques.