@article{AM2_1983__26_136991,
     author = {Howard E. Bell},
     title = {On commutativity of {P.I.} rings. {(Short} {Communication).}},
     journal = {Aequationes mathematicae},
     pages = {121--121},
     publisher = {mathdoc},
     volume = {26},
     year = {1983},
     url = {http://geodesic.mathdoc.fr/item/AM2_1983__26_136991/}
}