%0 Journal Article %A David Jerison %T Regularity of the Poisson kernel and free boundary problems %J Colloquium Mathematicum %D 1990 %P 547-568 %V 60 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/cm-60-61-2-547-568/ %R 10.4064/cm-60-61-2-547-568 %G en %F 10_4064_cm_60_61_2_547_568