Books by Frank Longo

The vast majority of sudoku puzzles that are labeled "hard," "expert," "challenger," are not really all that difficult. And in a surprising number of cases, they are downright easy. Part of the "Absolutely Nasty Sudoku" series, this book features basic and intermediate puzzles and techniques.

You say you can't get enough sudoku? Challenge accepted! With more than 900 puzzles at all difficulty levels (gradually increasing from easy to medium to hard), this massive collection should be enough sudoku for anyone for a while, anyway.

These 77 puzzles will introduce kids to the challenging and rewarding fun of sudoku.

Go way beyond difficult, with the hardest, most brain-busting sudoku you've ever seen!

Suitable for puzzle lovers, this title includes 300 puzzles.

The vast majority of sudoku puzzles that are labeled "hard," "expert," "challenger," are not really all that difficult. And in a surprising number of cases, they are downright easy. Part of the "Absolutely Nasty Sudoku" series, this book features basic and intermediate puzzles and techniques.

The vast majority of sudoku puzzles that are labeled "hard," "expert," "challenger," are not really all that difficult. And in a surprising number of cases, they are downright easy. Part of the "Absolutely Nasty Sudoku" series, this book features basic and intermediate puzzles and techniques.

This edition seeks to provide the reader with a coherent, concise introduction to the subject. An attempt is made to synthesize the explosion of information during the early 1990s about the different phases of fertilization.

Taking a page from karate - another Japanese art - each title in the series is graded by colour: White Belt for easy, Green Belt for medium level, Brown Belt for hard, and Black Belt for the super-tough solvers.