%0 Journal Article %A N. V. Efimov %A V. A. Zalgaller %A A. V. Pogorelov %T Aleksandr Danilovich Aleksandrov (on his fiftieth birthday) %J Trudy Matematicheskogo Instituta imeni V.A. Steklova %D 1962 %P 127-141 %V 17 %N 6 %I mathdoc %U http://geodesic.mathdoc.fr/item/RM_1962_17_6_a1/ %G en %F RM_1962_17_6_a1