@article{KUTGS_1976_9_a11,
     author = {B. A. Rozenfel'd and I. V. Kunakova},
     title = {Hyperbolic spaces of fractional index, and quasi-elliptic spaces of fractional defect},
     journal = {Trudy Geometricheskogo Seminara},
     pages = {88--104},
     year = {1976},
     volume = {9},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/KUTGS_1976_9_a11/}
}