@article{00763842, title = {On operators of Saphar type.}, journal = {Portugaliae Mathematica. Nova S\'erie}, volume = {51}, year = {1994}, pages = {617-628}, zbl = {0823.47003}, language = {en}, url = {http://dml.mathdoc.fr/item/00763842} }
Schmoeger, Christoph. On operators of Saphar type.. Portugaliae Mathematica. Nova Série, Tome 51 (1994) pp. 617-628. http://gdmltest.u-ga.fr/item/00763842/