@article{MZ_1982__180_173208,
     author = {K.R. Goodearl and R.B. Jr. Warfield},
     title = {Primitivity in {Differential} {Operator} {Rings.}},
     journal = {Mathematische Zeitschrift},
     pages = {503--524},
     publisher = {mathdoc},
     volume = {180},
     year = {1982},
     zbl = {0495.16002},
     url = {http://geodesic.mathdoc.fr/item/MZ_1982__180_173208/}
}