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@article{IVM_1982_11_a4, author = {Yu. B. Ermolaev}, title = {On the question of {Cartan} prolongations}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {30--40}, publisher = {mathdoc}, number = {11}, year = {1982}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1982_11_a4/} }
Yu. B. Ermolaev. On the question of Cartan prolongations. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 11 (1982), pp. 30-40. http://geodesic.mathdoc.fr/item/IVM_1982_11_a4/