@article{GDZPPN002330520, title = {Lower Bounds for Eigenfunctions on Riemannian Manifolds.}, journal = {Mathematische Annalen}, volume = {277}, year = {1987}, pages = {653-672}, zbl = {0619.58038}, url = {http://dml.mathdoc.fr/item/GDZPPN002330520} }
Donnelly, Harold. Lower Bounds for Eigenfunctions on Riemannian Manifolds.. Mathematische Annalen, Tome 277 (1987) pp. 653-672. http://gdmltest.u-ga.fr/item/GDZPPN002330520/