@article{DE_1985_21_3_a25,
     author = {T. N. Sysoeva},
     title = {A singularly perturbed boundary value problem of hyperbolic type},
     journal = {Differencialʹnye uravneni\^a},
     pages = {531--533},
     publisher = {mathdoc},
     volume = {21},
     number = {3},
     year = {1985},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1985_21_3_a25/}
}