I have been looking at exercise 9.12 on page 175. After a while I began to think that it must contain some errors and finally decided that the errors mentioned on the Oxford University web site - here, which point out that and on lines 12 and 13 of the same page should be interchanged, also apply to the exercise at the foot of the page.

This makes sense because the exercise is referenced on line 15.

So, according to me, exercise [9.12] should read:

Why does 'holomorphic functions on , reduced modulo holomorphic functions on ' become the definition of a hyperfunction that we had previously, when splits into and ?

However I think it would be easier to understand if it were written as:

When splits into and , why does the phrase - 'holomorphic functions on , reduced modulo holomorphic functions on ' - become the definition of a hyperfunction that we had previously?