Dear all,
There was a small typo in exercise bonus of series 9. We had $A'=\mathbb{Z}[\sqrt{-d}]$ and $F'=\mathbb{Q}[\sqrt{-d}]$ but they actually are $A'=\mathbb{Z}[\sqrt{-d'}]$ and $F'=\mathbb{Q}[\sqrt{-d'}]$.
The correct version of the exercise is now on moodle.
Best wishes,
Stefania
