A Kirchhoff equation with infinite conservation laws

We show here that the quasilinear Kirchhoff-Pokhozhaev equation $$u_{tt}-(a{\int }_{{\mathbb{R}}^n}\mathrm{\mid }\mathrm{\nabla }u{\mathrm{\mid }}^{2}dx+b{)}^{-2}\mathrm{\Delta }u=0,$$ with $a\mathrm{\ne }0$, admits conservation laws of all orders.