Voir la notice de l'article provenant de la source European Digital Mathematics Library
@article{MZ_1930__31_168177, author = {L. Lichtenstein}, title = {Zum {Sturm-Liouvilleschen} {Problem}}, journal = {Mathematische Zeitschrift}, pages = {346--349}, publisher = {mathdoc}, volume = {31}, year = {1930}, zbl = {55.0259.02}, url = {http://geodesic.mathdoc.fr/item/MZ_1930__31_168177/} }
L. Lichtenstein. Zum Sturm-Liouvilleschen Problem. Mathematische Zeitschrift, Tome 31 (1930), pp. 346-349. http://geodesic.mathdoc.fr/item/MZ_1930__31_168177/