@article{DAN_1957_114_6_a2,
     author = {V. M. Volosov},
     title = {Solutions of second order non-linear differential equations with slowly varying coefficients},
     journal = {Doklady Akademii Nauk},
     pages = {1149--1152},
     publisher = {mathdoc},
     volume = {114},
     number = {6},
     year = {1957},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1957_114_6_a2/}
}