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@article{DAN_1973_209_4_a2, author = {M. A. Gol'dman and S. N. Krachkovskii}, title = {On the stability of some properties of a closed linear operator}, journal = {Doklady Akademii Nauk}, pages = {769--772}, publisher = {mathdoc}, volume = {209}, number = {4}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1973_209_4_a2/} }
M. A. Gol'dman; S. N. Krachkovskii. On the stability of some properties of a closed linear operator. Doklady Akademii Nauk, Tome 209 (1973) no. 4, pp. 769-772. http://geodesic.mathdoc.fr/item/DAN_1973_209_4_a2/