@article{SMJ2_2003_29_4_a3,
     author = {Wirths, Karl-Joachim},
     title = {The {Koebe} {Domain} for {Concave} {Univalent} {Functions}},
     journal = {Serdica Mathematical Journal},
     pages = {355--360},
     publisher = {mathdoc},
     volume = {29},
     number = {4},
     year = {2003},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SMJ2_2003_29_4_a3/}
}