@article{IVM_2010_9_a1,
     author = {P. D. Andreev},
     title = {A. {D.~Alexandrov's} problem for non-positively curved spaces in the sense of {Busemann}},
     journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika},
     pages = {10--35},
     year = {2010},
     number = {9},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/IVM_2010_9_a1/}
}