Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DE_1973_9_8_a1, author = {\`E. F. Gasinskaya and K. S. Sibirskii}, title = {Affine invariants of a system with quadratic nonlinearities}, journal = {Differencialʹnye uravneni\^a}, pages = {1371--1382}, publisher = {mathdoc}, volume = {9}, number = {8}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1973_9_8_a1/} }
È. F. Gasinskaya; K. S. Sibirskii. Affine invariants of a system with quadratic nonlinearities. Differencialʹnye uravneniâ, Tome 9 (1973) no. 8, pp. 1371-1382. http://geodesic.mathdoc.fr/item/DE_1973_9_8_a1/