TY - JOUR AU - N. N. Ural'tseva TI - $C^1$ regularity of the boundary of a noncoincident set in a problem with an obstacle JO - Algebra i analiz PY - 1996 SP - 205 EP - 221 VL - 8 IS - 2 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/AA_1996_8_2_a11/ LA - ru ID - AA_1996_8_2_a11 ER -