TY - JOUR AU - S. N. Kudryavtsev TI - Approximation of a partial differential operator by bounded operators on a class of functions of finite smoothness JO - Sbornik. Mathematics PY - 1996 SP - 385 EP - 402 VL - 187 IS - 3 UR - http://geodesic.mathdoc.fr/item/SM_1996_187_3_a3/ LA - en ID - SM_1996_187_3_a3 ER -