@article{1077465191, author = {Kaplansky, Irving}, title = {Products of normal operators}, journal = {Duke Math. J.}, volume = {20}, number = {1}, year = {1953}, pages = { 257-260}, language = {en}, url = {http://dml.mathdoc.fr/item/1077465191} }
Kaplansky, Irving. Products of normal operators. Duke Math. J., Tome 20 (1953) no. 1, pp. 257-260. http://gdmltest.u-ga.fr/item/1077465191/