@article{1103040107,
author = {Weinberger, H. F.},
title = {Lower bounds for higher eigenvalues by finite difference methods.},
journal = {Pacific J. Math.},
volume = {8},
number = {4},
year = {1958},
pages = { 339-368},
language = {en},
url = {http://dml.mathdoc.fr/item/1103040107}
}
Weinberger, H. F. Lower bounds for higher eigenvalues by finite difference methods.. Pacific J. Math., Tome 8 (1958) no. 4, pp. 339-368. http://gdmltest.u-ga.fr/item/1103040107/