This is a class set of 10 books. Translated from the German. "When an inventive mouse misses the biggest cheese festival the world has ever seen, he's determined to turn back the clock. But what is time, and can it be influenced? With the help of a mouse clockmaker, a lot of inventiveness, and the notes of a certain famous Swiss physicist he succeeds in traveling back in time. But when he misses his goal by eighty years, the only one who can help is an employee of the Swiss Patent Office, who turned our concept of space and time upside down."

https://www.teachingbooks.net/qlsjbst. .