@article{1103043237, author = {Putnam, C. R.}, title = {On semi-normal operators.}, journal = {Pacific J. Math.}, volume = {7}, number = {4}, year = {1957}, pages = { 1649-1652}, language = {en}, url = {http://dml.mathdoc.fr/item/1103043237} }
Putnam, C. R. On semi-normal operators.. Pacific J. Math., Tome 7 (1957) no. 4, pp. 1649-1652. http://gdmltest.u-ga.fr/item/1103043237/