“…If one considers the following weakly damped Klein‐Gordon equation in place of , one has many previous papers, and one can cite D'Abbicco, da‐Luz‐Ikehata‐Charão, Zuazua, and the references therein (for nondamped Klein‐Gordon equations, one can cite several papers due to Nunes‐Bastos and the references therein concerning the local energy decay property and its related research). In this connection, in D'Abbicco, a more generalized evolution equations are studied: however, his result due to D'Abbicco, , theorem 4.1 which is close relation to ours, does not investigate the case of σ = α = 1 and μ = 0 much less decay estimates from below.…”