TürkmenE. “$\scr{Z^{ \ast}}$ - Semilocal Modules and the Proper Class $\scr{RS}$”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 71, no. 3, Mar. 2019, pp. 400-11, https://umj.imath.kiev.ua/index.php/umj/article/view/1447.