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@article{DE_1967_3_4_a5, author = {O. A. Liskovets}, title = {Incorrect problems with a closed non-invertible operator}, journal = {Differencialʹnye uravneni\^a}, pages = {636--646}, publisher = {mathdoc}, volume = {3}, number = {4}, year = {1967}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1967_3_4_a5/} }
O. A. Liskovets. Incorrect problems with a closed non-invertible operator. Differencialʹnye uravneniâ, Tome 3 (1967) no. 4, pp. 636-646. http://geodesic.mathdoc.fr/item/DE_1967_3_4_a5/