@article{DE_1982_18_1_a0,
     author = {V. F. Volkodavov and N. Ya. Nikolaev},
     title = {The local extremum principle for a hyperbolic equation and its application},
     journal = {Differencialʹnye uravneni\^a},
     pages = {3--7},
     publisher = {mathdoc},
     volume = {18},
     number = {1},
     year = {1982},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1982_18_1_a0/}
}