Voir la notice de l'article provenant de la source Math-Net.Ru
@article{MMO_1960_9_a1, author = {V. B. Lidskii}, title = {A non-selfadjoint operator of {Sturm-Liouville} type with a discrete spectrum}, journal = {Trudy Moskovskogo matemati\v{c}eskogo ob\^{s}estva}, pages = {45--79}, publisher = {mathdoc}, volume = {9}, year = {1960}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MMO_1960_9_a1/} }
V. B. Lidskii. A non-selfadjoint operator of Sturm-Liouville type with a discrete spectrum. Trudy Moskovskogo matematičeskogo obŝestva, Trudy Moskovskogo Matematicheskogo Obshchestva, Tome 9 (1960), pp. 45-79. http://geodesic.mathdoc.fr/item/MMO_1960_9_a1/