@article{DE_1972_8_6_a20,
     author = {A. G. Katranov},
     title = {The asymptotic behavior of oscillating solutions of the equation $\ddot x+f(t,\,x)g(\dot x)=0$},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1111--1115},
     publisher = {mathdoc},
     volume = {8},
     number = {6},
     year = {1972},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1972_8_6_a20/}
}