@article{GDZPPN002437082, title = {Negative Curvature and Embedded Eigenvalues.}, journal = {Mathematische Zeitschrift}, volume = {205}, year = {1990}, pages = {301-308}, zbl = {0699.53052}, url = {http://dml.mathdoc.fr/item/GDZPPN002437082} }
Donnelly, Harold. Negative Curvature and Embedded Eigenvalues.. Mathematische Zeitschrift, Tome 205 (1990) pp. 301-308. http://gdmltest.u-ga.fr/item/GDZPPN002437082/