TY - JOUR AU - N. V. Efimov AU - V. A. Zalgaller AU - A. V. Pogorelov TI - Aleksandr Danilovich Aleksandrov (on his fiftieth birthday) JO - Trudy Matematicheskogo Instituta imeni V.A. Steklova PY - 1962 SP - 127 EP - 141 VL - 17 IS - 6 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/RM_1962_17_6_a1/ LA - en ID - RM_1962_17_6_a1 ER -