p. (x) l. 5, “Chapter 4” should read “Chapter 6”. p. 24–25: As it stands, the proof of Lemma 2.2.3 is wrong, because ψ is not necessarily surjective. However, if P is a finitely generated projective module, then the proof works. So at the beginning of the section, one should make the further observation that P = F ′(ΓΓ) is a finitely generated projective module. This is because among all projec...