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@article{DE_1983_19_12_a0, author = {L. Ya. Adrianova}, title = {The structure of the {Persidski{\v\i}} spectrum of a second-order linear system}, journal = {Differencialʹnye uravneni\^a}, pages = {2027--2031}, publisher = {mathdoc}, volume = {19}, number = {12}, year = {1983}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1983_19_12_a0/} }
L. Ya. Adrianova. The structure of the Persidski{\v\i} spectrum of a second-order linear system. Differencialʹnye uravneniâ, Tome 19 (1983) no. 12, pp. 2027-2031. http://geodesic.mathdoc.fr/item/DE_1983_19_12_a0/