%0 Journal Article %A Schwerdtfeger, H. %T On the Discriminant x'Ax.y'Ay-(x'Ay)2 %J Canadian mathematical bulletin %D 1958 %P 175-179 %V 1 %N 3 %U http://geodesic.mathdoc.fr/articles/10.4153/CMB-1958-018-0/ %R 10.4153/CMB-1958-018-0 %F 10_4153_CMB_1958_018_0