@article{DE_1978_14_12_a3,
     author = {\`E. I. Grudo},
     title = {The stability of characteristic vectors of the solutions of linear homogeneous {Pfaffian} systems},
     journal = {Differencialʹnye uravneni\^a},
     pages = {2136--2146},
     publisher = {mathdoc},
     volume = {14},
     number = {12},
     year = {1978},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1978_14_12_a3/}
}