@article{DE_1995_31_11_a9,
     author = {A. P. Krishchenko},
     title = {Localization of limit cycles},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1858--1865},
     year = {1995},
     volume = {31},
     number = {11},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1995_31_11_a9/}
}