@article{oai:tsukuba.repo.nii.ac.jp:00016113,
 author = {Katayama, Hisao},
 issue = {1},
 journal = {Tsukuba Journal of Mathematics},
 month = {Jun},
 pages = {67--83},
 title = {A study of rings with trivial preradical ideals},
 volume = {5},
 year = {1981}
}