@article{1103034364, author = {Gilbert, Richard C.}, title = {Extremal spectral functions of a symmetric operator.}, journal = {Pacific J. Math.}, volume = {14}, number = {4}, year = {1964}, pages = { 75-84}, language = {en}, url = {http://dml.mathdoc.fr/item/1103034364} }
Gilbert, Richard C. Extremal spectral functions of a symmetric operator.. Pacific J. Math., Tome 14 (1964) no. 4, pp. 75-84. http://gdmltest.u-ga.fr/item/1103034364/