%0 Journal Article %A P. Mammone %A J.-P. Tignol %A A. Wadsworth %T Fields of characteristic 2 with prescribed u-invariants. %J Mathematische Annalen %D 1991 %P 109-128 %V 290 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/MAN_1991__290_4_164813/ %F MAN_1991__290_4_164813