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@article{DE_1994_30_2_a22, author = {N. B. Uskova}, title = {On the spectrum of some classes of differential operators}, journal = {Differencialʹnye uravneni\^a}, pages = {350--352}, publisher = {mathdoc}, volume = {30}, number = {2}, year = {1994}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1994_30_2_a22/} }
N. B. Uskova. On the spectrum of some classes of differential operators. Differencialʹnye uravneniâ, Tome 30 (1994) no. 2, pp. 350-352. http://geodesic.mathdoc.fr/item/DE_1994_30_2_a22/