@article{DE_1993_29_12_a4,
     author = {I. S. Lomov},
     title = {Small denominators in the analytic theory of degenerate differential equations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {2079--2089},
     publisher = {mathdoc},
     volume = {29},
     number = {12},
     year = {1993},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1993_29_12_a4/}
}