@article{SM_1976_28_2_a1,
     author = {Yu. S. Il'yashenko},
     title = {Analytic unsolvability of the stability problem and the problem of topological classification of the singular points of analytic systems of differential equations},
     journal = {Sbornik. Mathematics},
     pages = {140--152},
     publisher = {mathdoc},
     volume = {28},
     number = {2},
     year = {1976},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1976_28_2_a1/}
}