@article{CMH_1982__57_139904,
     author = {F.W. Gehring},
     title = {Injectivity of local quasi-isometries.},
     journal = {Commentarii mathematici Helvetici},
     pages = {202--220},
     publisher = {mathdoc},
     volume = {57},
     year = {1982},
     zbl = {0528.30010},
     url = {http://geodesic.mathdoc.fr/item/CMH_1982__57_139904/}
}