Mutation in triangulated categories and rigid Cohen-Macaulay modules
  We introduce the notion of mutation of $n$-cluster tilting subcategories in a triangulated category with Auslander-Reiten-Serre duality. Using this idea, we are able to obtain the complete classifications of rigid Cohen-Macaulay modules over certain Veronese subrings. 
Osamu Iyama, Yuji Yoshino