@article{DAN_1967_176_1_a10,
     author = {S. Ya. Yakubov},
     title = {Nonlinear abstract hyperbolic equations},
     journal = {Doklady Akademii Nauk},
     pages = {46--49},
     publisher = {mathdoc},
     volume = {176},
     number = {1},
     year = {1967},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1967_176_1_a10/}
}