@article{DE_1983_19_4_a28,
     author = {V. S. Mokeichev},
     title = {In the perturbation of a boundary value problem by terms with deviating argument the spectrum can vanish},
     journal = {Differencialʹnye uravneni\^a},
     pages = {717--718},
     publisher = {mathdoc},
     volume = {19},
     number = {4},
     year = {1983},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1983_19_4_a28/}
}