@article{DE_1994_30_12_a0,
     author = {B. N. Biyarov},
     title = {On the spectral properties of well-posed restrictions and extensions of the {Sturm--Liouville} operator},
     journal = {Differencialʹnye uravneni\^a},
     pages = {2027--2032},
     publisher = {mathdoc},
     volume = {30},
     number = {12},
     year = {1994},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1994_30_12_a0/}
}