@article{10_4171_dm_283,
     author = {Gelu Popescu},
     title = {Hyperbolic geometry on noncommutative balls},
     journal = {Documenta mathematica},
     pages = {595--651},
     year = {2009},
     volume = {14},
     doi = {10.4171/dm/283},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/dm/283/}
}