@article{DE_1975_11_3_a4,
     author = {I. V. Pehenko},
     title = {Estimates of the solutions of ordinary differential equations with a small parameter multiplying the highest derivative},
     journal = {Differencialʹnye uravneni\^a},
     pages = {456--461},
     publisher = {mathdoc},
     volume = {11},
     number = {3},
     year = {1975},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1975_11_3_a4/}
}