@article{IVM_1992_9_a1,
     author = {S. A. Vavilov and S. V. Yukhnevich},
     title = {Periodic solutions of autonomous systems},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {13--15},
     publisher = {mathdoc},
     number = {9},
     year = {1992},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_1992_9_a1/}
}