@article{CMH_1977__52_139719,
     author = {Friedrich Huckemann},
     title = {An extremal problem for harmonic measure.},
     journal = {Commentarii mathematici Helvetici},
     pages = {611--624},
     year = {1977},
     volume = {52},
     zbl = {0379.30010},
     url = {http://geodesic.mathdoc.fr/item/CMH_1977__52_139719/}
}