DokuchaevM. A., and KirichenkoV. V. 2002. “Quasi-Frobenius Rings and Nakayama Permutations of Semiperfect Rings”. Ukrains’kyi Matematychnyi Zhurnal 54 (7), 919-30. https://umj.imath.kiev.ua/index.php/umj/article/view/4128.