Librería Samer Atenea
Kálamo Books
Librería Elías (Asturias)
Librería Kolima (Madrid)
Librería Proteo (Málaga)
Teaching could easily be one of the most stressful professions because you are dealing with a class of different personalities. Sudoku helps you to beat stress and handle every class with renewed vigor. Keep a copy of this Sudoku book with you. Take it out and solve a puzzle whenever you feel the need to. Good luck!