TY - JOUR AU - A. A. Zlotnik AU - I. D. Turetaev TI - Sharp estimates for error and optimality of two-layered efficient JO - Doklady Akademii Nauk PY - 1983 SP - 1306 EP - 1311 VL - 272 IS - 6 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/DAN_1983_272_6_a6/ LA - ru ID - DAN_1983_272_6_a6 ER -