@article{MZM_1993_54_6_a15,
     author = {A. R. Shirikyan},
     title = {On classical almost-periodic solutions of nonlinear hyperbolic equations},
     journal = {Matemati\v{c}eskie zametki},
     pages = {146--148},
     publisher = {mathdoc},
     volume = {54},
     number = {6},
     year = {1993},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1993_54_6_a15/}
}