Librería Samer Atenea
Librería Aciertas (Toledo)
Kálamo Books
Librería Perelló (Valencia)
Librería Elías (Asturias)
Donde los libros
Librería Kolima (Madrid)
Librería Proteo (Málaga)
Check the sample puzzle on the back page to judge the difficulty!Go beyond simple sudoku with this collection of diabolical sudoku puzzles in a travel-sized format of 8x5 inches.1 large print puzzle per page for easy visibility and space for notes.You will need strategies like X-Cycles, BUG, XY-Chain, X-Wing, Simple Coloring, Y-Wing, Swordfish & XYZ Wing amongst others to solve the most difficult puzzles possible.