@article{1102971637, author = {Kuttler, J. R.}, title = {Upper and lower bounds for eigenvalues by finite differences.}, journal = {Pacific J. Math.}, volume = {35}, number = {3}, year = {1970}, pages = { 429-440}, language = {en}, url = {http://dml.mathdoc.fr/item/1102971637} }
Kuttler, J. R. Upper and lower bounds for eigenvalues by finite differences.. Pacific J. Math., Tome 35 (1970) no. 3, pp. 429-440. http://gdmltest.u-ga.fr/item/1102971637/