13C99 16D10; 16D40; 16D80 16D80 16U80 Rickart module Rickart modules \(\delta\)-semiperfect modules \(\delta\)-supplemented modules \(\mathrm{Rad}(\cdot)\)-inverse split module \(\mathrm{Soc}(\cdot)\)-inverse split module abelian modules principally \(\delta\)-semiperfect modules principally \(\delta\)-supplemented modules principally projective modules reduced modules rigid modules semicommutative modules semiperfect modules supplemented modules symmetric modules