2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/67353Using Walters' version of the Ruelle-Perron-Frobenius Theorem we show the existence and uniqueness of KMS states for a certain one-parameter group of automorphisms on a C*-algebra associated to a positively expansive map on a compact metric space.9 pages, minor changes, submitted to Proceedings of the AMSOperator Algebras46L30, 46L40, 46L55text