@article{DE_1969_5_11_a8,
     author = {V. E. Chernyshev},
     title = {The absence of smooth invariant tori with irrational rotation number for systems of differential equations with smoothly stable structure},
     journal = {Differencialʹnye uravneni\^a},
     pages = {2034--2040},
     year = {1969},
     volume = {5},
     number = {11},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1969_5_11_a8/}
}