“…The existence of almost periodic solutions to second-order differential equations constitutes one of the most important topics in qualitative theory of differential equations due essentially to their applications such thermoelastic plate equations [12,37] or telegraph equation [43] or Sine-Gordon equations [36]. Some contributions on the maximal regularity, bounded, almost periodic, asymptotically almost periodic solutions to abstract second-order differential and partial differential equations have recently been made, among them are [9], [10], [18], [20], [29], [30], [39], [40], [52], [53], [54], [55], and [56].…”