%0 Journal Article %A Rainer Schimming %T Harmonic Differential Operators. %J Forum mathematicum %D 1991 %P 177-204 %V 3 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/FORUM_1991__3_2_186389/ %F FORUM_1991__3_2_186389