@article{DE_1994_30_5_a8,
     author = {Ak. B. Bazarbekov and Ar. B. Bazarbekov},
     title = {Goursat and {Darboux} problems for the two-dimensional wave equation. {I}},
     journal = {Differencialʹnye uravneni\^a},
     pages = {806--813},
     publisher = {mathdoc},
     volume = {30},
     number = {5},
     year = {1994},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1994_30_5_a8/}
}