@article{DE_1980_16_3_a8,
     author = {V. P. Skripnik},
     title = {Degenerate systems and a small parameter multiplying the derivative},
     journal = {Differencialʹnye uravneni\^a},
     pages = {454--461},
     publisher = {mathdoc},
     volume = {16},
     number = {3},
     year = {1980},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1980_16_3_a8/}
}