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For a self-injective finite-dimensional algebra, remove the projective vertices from its Auslander–Reiten quiver. The resulting stable quiver has vertices the nonprojective indecomposable modules. Its translation sends the end term of an almost-split exact sequence to its start term. In particular a quiver of shape $\mathbb{Z}{A}_s/⟨{\tau }^e⟩$ has $es$ vertices.