“…In Liu and Chen, 13 they discussed the equation including the memory term for ∂ ν u t on Γ 0 , and also with the viscoelastic term Δ u t in the domain Ω. Liu and Sun 14 studied the following problem: With the perturbed energy functional technique, they established a general decay result relying on the behavior of both α ( t ) and g ( t ). Motivated by Jeong et al, Liu, Chen, and Sun, 9,13,14 we intend to study the energy decay rate of () with Lyapunov approach in the framework of Riemannian geometry. Then, as an application, we get the exponential stabilization of the wave equations with memory type acoustic boundar...…”