On the stable module category of a self-injective algebra
Karin Erdmann and Otto Kerner. 
Trans. Amer. Math. Soc. 352 (2000), 2389-2405.

Abstract: Let $\Lambda$ be a finite-dimensional self-injective algebra. We 
study the dimensions of spaces of stable homomorphisms between 
indecomposable $\Lambda$-modules which belong to Auslander-Reiten 
components of the form $\mathbf Z A_\infty$ or $\mathbf Z A_\infty/\langle
\tau^k \rangle$. The results are applied to representations of finite 
groups over fields of prime characteristic, especially blocks of wild 
representation type.