TY - JOUR AU - A. G. Popov TI - A geometric approach to the interpretation of solutions of the JO - Doklady Akademii Nauk PY - 1990 SP - 1109 EP - 1111 VL - 312 IS - 5 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/DAN_1990_312_5_a19/ LA - ru ID - DAN_1990_312_5_a19 ER -