@article{DE_1999_35_1_a13,
     author = {S. A. Mazanik},
     title = {Lappo-Danilevskiǐ systems in the set of linear systems},
     journal = {Differencialʹnye uravneni\^a},
     pages = {90--96},
     year = {1999},
     volume = {35},
     number = {1},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1999_35_1_a13/}
}