@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/}
}