%0 Journal Article %A Yu. A. Aminov %T Three-dimensional saddle hypersurfaces with a~constant second symmetric function of principal curvatures %J Izvestiâ vysših učebnyh zavedenij. Matematika %D 1992 %P 15-20 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/IVM_1992_6_a1/ %G ru %F IVM_1992_6_a1