@article{CMH_1954__28_139085,
     author = {A. Wintner and S.-S- Chern and P. Hartman},
     title = {On {Isothermic} {Coordinates.}},
     journal = {Commentarii mathematici Helvetici},
     pages = {301--309},
     publisher = {mathdoc},
     volume = {28},
     year = {1954},
     zbl = {0056.40206},
     url = {http://geodesic.mathdoc.fr/item/CMH_1954__28_139085/}
}