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@article{DAN_1982_265_5_a12, author = {B. Yu. Sternin}, title = {On differential equations of subprincipal type}, journal = {Doklady Akademii Nauk}, pages = {1078--1081}, publisher = {mathdoc}, volume = {265}, number = {5}, year = {1982}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1982_265_5_a12/} }
B. Yu. Sternin. On differential equations of subprincipal type. Doklady Akademii Nauk, Tome 265 (1982) no. 5, pp. 1078-1081. http://geodesic.mathdoc.fr/item/DAN_1982_265_5_a12/