@article{DE_2000_36_8_a13,
     author = {S. S. Kharibegashvili},
     title = {On the statement of characteristic problems for symmetric first-order hyperbolic systems},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1113--1122},
     publisher = {mathdoc},
     volume = {36},
     number = {8},
     year = {2000},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_2000_36_8_a13/}
}