%0 Journal Article %A Hing-Sun Luk %T Normalization of Differential Equations Defining a CR Structure. %J Inventiones mathematicae %D 1978 %P 33-60 %V 48 %I mathdoc %U http://geodesic.mathdoc.fr/item/IM_1978__48_142583/ %F IM_1978__48_142583