@article{1102982796, author = {Howland, James S.}, title = {Embedded eigenvalues and virtual poles.}, journal = {Pacific J. Math.}, volume = {31}, number = {3}, year = {1969}, pages = { 565-582}, language = {en}, url = {http://dml.mathdoc.fr/item/1102982796} }
Howland, James S. Embedded eigenvalues and virtual poles.. Pacific J. Math., Tome 31 (1969) no. 3, pp. 565-582. http://gdmltest.u-ga.fr/item/1102982796/