@article{DE_1989_25_9_a11,
     author = {A. B. Bazarbekov},
     title = {Boundary value problems for the two-dimensional wave equation in a characteristic cone},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1551--1556},
     publisher = {mathdoc},
     volume = {25},
     number = {9},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1989_25_9_a11/}
}