@article{TM_2012_278_a18,
     author = {Ludmila S. Pulkina},
     title = {Problems with nonlinear boundary conditions for a~hyperbolic equation},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {208--216},
     publisher = {mathdoc},
     volume = {278},
     year = {2012},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TM_2012_278_a18/}
}