@article{DE_1975_11_9_a23,
     author = {Yu. A. Ryabov and M. F. Korolev},
     title = {Letter to the editors: {{\textquotedblleft}The} construction of periodic solutions of certain linear and quasilinear equations{\textquotedblright} {(Differencial'nye} {Uravnenija} 11 (1975), 280{\textendash}286)},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1713},
     year = {1975},
     volume = {11},
     number = {9},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1975_11_9_a23/}
}