@article{DE_1985_21_6_a28,
     author = {P. A. Mishnaevskii},
     title = {Length of the gaps in the continuous spectrum of the {Sturm--Liouville} operator},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1095--1097},
     publisher = {mathdoc},
     volume = {21},
     number = {6},
     year = {1985},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1985_21_6_a28/}
}