@article{DE_1983_19_11_a23,
     author = {L. A. Kalyakin},
     title = {Construction of an asymptotic expansion of the solution of a hyperbolic equation with a weakly nonlinear perturbation},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1991--1992},
     publisher = {mathdoc},
     volume = {19},
     number = {11},
     year = {1983},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1983_19_11_a23/}
}