@article{CMH_1962__37_139244,
     author = {Edgar Reich},
     title = {On a characterization of quasiconformal mappings.},
     journal = {Commentarii mathematici Helvetici},
     pages = {44--48},
     publisher = {mathdoc},
     volume = {37},
     year = {1962},
     zbl = {0108.07701},
     url = {http://geodesic.mathdoc.fr/item/CMH_1962__37_139244/}
}