%0 Journal Article
%A El Haial, Abdelillah
%A Labbas, Rabah
%T On the ellipticity and solvability of an abstract second-order differential equation
%J Electronic Journal of Differential Equations
%D 2001
%V 2001
%I mathdoc
%U http://geodesic.mathdoc.fr/item/EJDE_2001__2001__a168/
%G en
%F EJDE_2001__2001__a168