TY - JOUR AU - O. Axelsson AU - L. Laayouni AU - S. Margenov TI - Robust Multilevel Preconditioners for Second Order Elliptic Equations and Systems of Equations JO - Mathematica balkanica PY - 2005 SP - 321 VL - 19 IS - 3-4 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/MABA_2005_19_3-4_a6/ ID - MABA_2005_19_3-4_a6 ER -