@article{1103036923, author = {Kreith, Kurt}, title = {The spectrum of singular self-adjoint elliptic operators.}, journal = {Pacific J. Math.}, volume = {11}, number = {4}, year = {1961}, pages = { 1401-1405}, language = {en}, url = {http://dml.mathdoc.fr/item/1103036923} }
Kreith, Kurt. The spectrum of singular self-adjoint elliptic operators.. Pacific J. Math., Tome 11 (1961) no. 4, pp. 1401-1405. http://gdmltest.u-ga.fr/item/1103036923/