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@article{DAN_1989_307_3_a1, author = {A. Yu. Veretennikov}, title = {Conditions for hypo-ellipticity and estimates for the rate of}, journal = {Doklady Akademii Nauk}, pages = {524--526}, publisher = {mathdoc}, volume = {307}, number = {3}, year = {1989}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1989_307_3_a1/} }
A. Yu. Veretennikov. Conditions for hypo-ellipticity and estimates for the rate of. Doklady Akademii Nauk, Tome 307 (1989) no. 3, pp. 524-526. http://geodesic.mathdoc.fr/item/DAN_1989_307_3_a1/