@article{DE_1985_21_10_a12,
     author = {A. N. Filatov},
     title = {Some problems of the theory of singularly perturbed equations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1726--1730},
     publisher = {mathdoc},
     volume = {21},
     number = {10},
     year = {1985},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1985_21_10_a12/}
}