Used book – Witch, Volume 3, Elisabetta Gnone, Elisabeth Lenhard, Agnès Piganiol

Will and her friends are going through a delicate period: it's not easy to stay united without squabbling when you're responsible for a mission as overwhelming as theirs. Yet new challenges await them... First, they must discover who is behind this overly kind math teacher. They also need to understand the purpose of this strange book found at Elyon's place.