@article{DE_1969_5_2_a16,
     author = {N. A. Lukashevich},
     title = {Functions which are definable by a certain system of differential equations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {379--381},
     publisher = {mathdoc},
     volume = {5},
     number = {2},
     year = {1969},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1969_5_2_a16/}
}