@article{DM_2002_14_3_a6,
     author = {N. B. Bezverkhnyaya},
     title = {Hyperbolicity of some 2-generator groups with one defining condition},
     journal = {Diskretnaya Matematika},
     pages = {54--69},
     publisher = {mathdoc},
     volume = {14},
     number = {3},
     year = {2002},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DM_2002_14_3_a6/}
}