@article{DAN_1974_216_1_a1,
     author = {A. B. Vasil'eva and V. A. Esipova},
     title = {Conditionally stable singularly perturbed systems},
     journal = {Doklady Akademii Nauk},
     pages = {17--20},
     publisher = {mathdoc},
     volume = {216},
     number = {1},
     year = {1974},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1974_216_1_a1/}
}