@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/}
}