%0 Journal Article %A Ma. Kato %T Compact Differentiable 4-Folds with Quaternionic Structures. %J Mathematische Annalen %D 1980 %P 79-96 %V 248 %I mathdoc %U http://geodesic.mathdoc.fr/item/MAN_1980__248_163369/ %F MAN_1980__248_163369