@article{DE_1984_20_8_a8,
     author = {V. A. Lunkevich and K. S. Sibirskii},
     title = {Integrals of a system with homogeneous nonlinearities of the third degree in cases of a center},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1360--1365},
     publisher = {mathdoc},
     volume = {20},
     number = {8},
     year = {1984},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1984_20_8_a8/}
}