@article{DE_1996_32_7_a2,
     author = {A. S. Shube},
     title = {Partial integrals, integrability and the center problem},
     journal = {Differencialʹnye uravneni\^a},
     pages = {880--888},
     publisher = {mathdoc},
     volume = {32},
     number = {7},
     year = {1996},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1996_32_7_a2/}
}