@article{DE_1988_24_10_a0,
     author = {V. V. Amel'kin and V. \`E. Zhavnerchik},
     title = {Periodic solutions of the {Li\'enard} equation},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1659--1662},
     publisher = {mathdoc},
     volume = {24},
     number = {10},
     year = {1988},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1988_24_10_a0/}
}