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