%0 Journal Article %A Bales, L. A. %T Semidiscrete and single step fully discrete finite element approximations for second order hyperbolic equations with nonsmooth solutions %J ESAIM: Modélisation mathématique et analyse numérique %D 1993 %P 55-63 %V 27 %N 1 %I AFCET - Gauthier-Villars %C Paris %U http://www.numdam.org/item/M2AN_1993__27_1_55_0/ %G en %F M2AN_1993__27_1_55_0