@article{10_4153_CJM_1991_025_3,
     author = {Riley, David M.},
     title = {Group {Rings} {With} {Hypercentral} {Unit} {Groups}},
     journal = {Canadian journal of mathematics},
     pages = {425--434},
     year = {1991},
     volume = {43},
     number = {2},
     doi = {10.4153/CJM-1991-025-3},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1991-025-3/}
}