@article{MZM_2012_91_4_a9,
     author = {D. A. Kovtonyuk and V. I. Ryazanov},
     title = {On the {Theory} of {Generalized} {Quasi-Isometries}},
     journal = {Matemati\v{c}eskie zametki},
     pages = {571--577},
     publisher = {mathdoc},
     volume = {91},
     number = {4},
     year = {2012},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_2012_91_4_a9/}
}