Voir la notice de l'article provenant de la source Math-Net.Ru
@article{MZM_1990_48_3_a2, author = {A. D. Bruno}, title = {System, similar to a~normal form}, journal = {Matemati\v{c}eskie zametki}, pages = {20--31}, publisher = {mathdoc}, volume = {48}, number = {3}, year = {1990}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1990_48_3_a2/} }
A. D. Bruno. System, similar to a~normal form. Matematičeskie zametki, Tome 48 (1990) no. 3, pp. 20-31. http://geodesic.mathdoc.fr/item/MZM_1990_48_3_a2/