@article{DE_1979_15_8_a4,
     author = {N. I. Vulpe},
     title = {Construction of a polynomial basis of comitants of a differential system},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1399--1410},
     publisher = {mathdoc},
     volume = {15},
     number = {8},
     year = {1979},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1979_15_8_a4/}
}