@article{IM2_1995_45_1_a1,
     author = {A. V. Zhiber},
     title = {Quasilinear hyperbolic equations with an infinite-dimensional symmetry algebra},
     journal = {Izvestiya. Mathematics },
     pages = {33--54},
     publisher = {mathdoc},
     volume = {45},
     number = {1},
     year = {1995},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1995_45_1_a1/}
}