@article{10_4153_CJM_1978_026_x,
     author = {Promislow, David},
     title = {Dimension of {Null} {Spaces} with {Applications} to {Group} {Rings}},
     journal = {Canadian journal of mathematics},
     pages = {289--300},
     year = {1978},
     volume = {30},
     number = {2},
     doi = {10.4153/CJM-1978-026-x},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1978-026-x/}
}