%0 Journal Article
%A Lebeau, Gilles
%T The wave equation with oscillating density : observability at low frequency
%J ESAIM: Control, Optimisation and Calculus of Variations
%D 2000
%P 219-258
%V 5
%I EDP-Sciences
%U http://www.numdam.org/item/COCV_2000__5__219_0/
%G en
%F COCV_2000__5__219_0