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@article{IVM_2005_6_a6, author = {E. N. Sosov}, title = {A tangent space in the sense of {Busemann}}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {71--75}, publisher = {mathdoc}, number = {6}, year = {2005}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_2005_6_a6/} }
E. N. Sosov. A tangent space in the sense of Busemann. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 6 (2005), pp. 71-75. http://geodesic.mathdoc.fr/item/IVM_2005_6_a6/