Cheri, P. V.P. V.CheriDey, DeblinaDeblinaDeyAkhil, K.K.AkhilKotal, NirmalNirmalKotalVeer, DharmDharmVeer2025-08-312025-08-312024-01-0110.7146/math.scand.a-1490332-s2.0-85209565685https://d8.irins.org/handle/IITG2025/29237In this article, we characterize Cohen-Macaulay permutation graphs. In particular, we show that a permutation graph is Cohen-Macaulay if and only if it is well-covered and there exists a unique way of partitioning its vertex set into r disjoint maximal cliques, where r is the cardinality of a maximal independent set of the graph. We also provide some sufficient conditions for a comparability graph to be a uniquely partially orderable (UPO) graph.falseArticle419-43120241arJournal1