The marked Black stone is mistaken shown as White in the book.
The theme of the problem is: Black will get an eye at the marked point, she must find a method of creating a second eye.
The marked point is not an eye. White will squeeze at 'a'. Black has only one eye.
If ,
-
kill. After
Black is damezumari. (Found by Jantje).
ferdi suggested this correction to the problem.