TY - JOUR AU - E. A. Zernyshkina TI - The Wirtinger–Steklov inequality between the norm of a periodic function and the norm of the positive cutoff of its derivative JO - Trudy Instituta matematiki i mehaniki PY - 2008 SP - 99 EP - 111 VL - 14 IS - 3 UR - http://geodesic.mathdoc.fr/item/TIMM_2008_14_3_a8/ LA - ru ID - TIMM_2008_14_3_a8 ER -