@article{CMH_1968__43_139368,
     author = {Robert J. Sibner},
     title = {Remarks on the {Koebe} {Kreisnormierungsproblem.}},
     journal = {Commentarii mathematici Helvetici},
     pages = {289--295},
     publisher = {mathdoc},
     volume = {43},
     year = {1968},
     zbl = {0172.37601},
     url = {http://geodesic.mathdoc.fr/item/CMH_1968__43_139368/}
}