@article{DE_1976_12_6_a9,
     author = {A. Ya. Khokhryakov},
     title = {An estimate of the eigenvalue that is smallest in absolute value for a certain periodic problem},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1028--1039},
     publisher = {mathdoc},
     volume = {12},
     number = {6},
     year = {1976},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1976_12_6_a9/}
}