@article{CMH_1943__16_138844,
     author = {J. Wolff and T. van Aardenne-Ehrenfest},
     title = {\"Uber die {Grenzen} der einfachzusammenh\"angenden {Gebiete.}},
     journal = {Commentarii mathematici Helvetici},
     pages = {321--323},
     publisher = {mathdoc},
     volume = {16},
     year = {1943},
     zbl = {0061.15504},
     url = {http://geodesic.mathdoc.fr/item/CMH_1943__16_138844/}
}