Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{MZ_1974__140_172128, author = {John Piepenbrink}, title = {Finiteness of the {Lower} {Spectrum} of {Schr\"odinger} {Operators.}}, journal = {Mathematische Zeitschrift}, pages = {29--40}, publisher = {mathdoc}, volume = {140}, year = {1974}, zbl = {0305.35076}, url = {http://geodesic.mathdoc.fr/item/MZ_1974__140_172128/} }
John Piepenbrink. Finiteness of the Lower Spectrum of Schrödinger Operators.. Mathematische Zeitschrift, Tome 140 (1974), pp. 29-40. http://geodesic.mathdoc.fr/item/MZ_1974__140_172128/