%0 Journal Article %A A. N. Varchenko %T Semicontinuity of the spectrum and an upper bound for the number of singular points of the projective hypersurface %J Doklady Akademii Nauk %D 1983 %P 1294-1297 %V 270 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1983_270_6_a1/ %G ru %F DAN_1983_270_6_a1