%0 Journal Article %T Sergei Petrovich Novikov (on his fiftieth birthday) %J Trudy Matematicheskogo Instituta imeni V.A. Steklova %D 1988 %P 1-10 %V 43 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/RM_1988_43_4_a0/ %G en %F RM_1988_43_4_a0