Covering techniques in Auslander-Reiten theory
  Given a finite dimensional algebra over a perfect field the text introduces covering functors over the mesh category of any modulated Auslander-Reiten component of the algebra. This is applied to study the composition of irreducible morphisms between indecomposable modules in relation with the powers of the radical of the module category. 
Claudia Chaio, Patrick Le Meur, Sonia Trepode
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