@article{00940801, title = {On a Darboux type multidimensional problem for second-order hyperbolic systems.}, journal = {Georgian Mathematical Journal}, volume = {3}, year = {1996}, pages = {363-378}, doi = {10.1007/BF02256725}, zbl = {0858.35077}, language = {en}, url = {http://dml.mathdoc.fr/item/00940801} }
Kharibegashvili, S. On a Darboux type multidimensional problem for second-order hyperbolic systems.. Georgian Mathematical Journal, Tome 3 (1996) pp. 363-378. doi : 10.1007/BF02256725. http://gdmltest.u-ga.fr/item/00940801/