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@article{FAA_1979_13_1_a6, author = {G. R. Belitskii}, title = {Invariant normal forms of formal series}, journal = {Funkcionalʹnyj analiz i ego prilo\v{z}eni\^a}, pages = {59--60}, publisher = {mathdoc}, volume = {13}, number = {1}, year = {1979}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/FAA_1979_13_1_a6/} }
G. R. Belitskii. Invariant normal forms of formal series. Funkcionalʹnyj analiz i ego priloženiâ, Tome 13 (1979) no. 1, pp. 59-60. http://geodesic.mathdoc.fr/item/FAA_1979_13_1_a6/