Refail AlizadeSerpil Güngör2025-10-06201813035010, 2651477X1303-501010.15672/HJMS.20154413844https://www.scopus.com/inward/record.uri?eid=2-s2.0-85073872124&doi=10.15672%2FHJMS.20154413844&partnerID=40&md5=2661061aa9ea772ab161d5b69e40f085https://gcris.yasar.edu.tr/handle/123456789/9607In this paper it is shown that a factor module of an ⊕-co-coatomically supplemented module is not in general ⊕-co-coatomically supplemented. If M is ⊕-co-coatomically supplemented and U is a fully invariant submodule of M then M/U is ⊕-co-coatomically supplemented. A ring R is left perfect if and only if R(N) is an ⊕-co-coatomically supplemented R-module. A projective module M is co-coatomically semiperfect if and only if M is ⊕-co-coatomically supplemented. A ring is semiperfect if and only if every finitely generated free R-module is co-coatomically semiperfect. © 2020 Elsevier B.V. All rights reserved.EnglishCo-coatomic Submodule, Co-coatomically Semiperfect Module, ⊕-co-coatomically Supplemented ModuleArticle