@article{CMH_1977__52_139715,
     author = {F.W. Gehring},
     title = {Univalent functions and the {Schwarzian} derivative.},
     journal = {Commentarii mathematici Helvetici},
     pages = {561--572},
     publisher = {mathdoc},
     volume = {52},
     year = {1977},
     zbl = {0373.30013},
     url = {http://geodesic.mathdoc.fr/item/CMH_1977__52_139715/}
}