TY  - JOUR
AU  - Cui, Yan
AU  - Laurent, Camille
AU  - Wang, Zhiqiang
TI  - On the observability inequality of coupled wave equations: the case without boundary
JO  - ESAIM: Control, Optimisation and Calculus of Variations
PY  - 2020
VL  - 26
PB  - EDP-Sciences
UR  - http://www.numdam.org/articles/10.1051/cocv/2020004/
DO  - 10.1051/cocv/2020004
LA  - en
ID  - COCV_2020__26_1_A14_0
ER  -