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@article{IVM_1988_12_a6, author = {G. O. \`El'sting}, title = {On the connection between {Cartan} prolongations of depth~2 and depth~1}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {49--50}, publisher = {mathdoc}, number = {12}, year = {1988}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1988_12_a6/} }
G. O. Èl'sting. On the connection between Cartan prolongations of depth~2 and depth~1. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 12 (1988), pp. 49-50. http://geodesic.mathdoc.fr/item/IVM_1988_12_a6/