@article{ZVMMF_1998_38_5_a4,
     author = {Kh. I. Botashev},
     title = {Construction of periodic solutions with a given accuracy by the method of the small parameter},
     journal = {\v{Z}urnal vy\v{c}islitelʹnoj matematiki i matemati\v{c}eskoj fiziki},
     pages = {728--733},
     publisher = {mathdoc},
     volume = {38},
     number = {5},
     year = {1998},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZVMMF_1998_38_5_a4/}
}