TY - JOUR AU - V. I. Burenkov TI - Approximation by infinitely differentiable functions with preservation of boundary values JO - Informatics and Automation PY - 1987 SP - 68 EP - 70 VL - 180 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/TRSPY_1987_180_a32/ LA - ru ID - TRSPY_1987_180_a32 ER -