@article{DAN_1968_183_4_a13,
     author = {V. I. Chekhlov},
     title = {A mixed problem with discontinuous boundary conditions for the wave equation},
     journal = {Doklady Akademii Nauk},
     pages = {787--790},
     publisher = {mathdoc},
     volume = {183},
     number = {4},
     year = {1968},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1968_183_4_a13/}
}