“…[1, 3, 14, 44, 46, 49-65, 69-80, 82-85, 87-90, 95-99, 101-107, 109, 116-118, 120, 122, 124, 125, 129-134, 136, 137, 140-149, 151-153, 156-158, 160-162, 164, 173-179, 187, 189, 190, 195-201, 207, 208, 212, 214, 217, 219, 221-223, 226, 228, 230, 236, 239-241, 262, 266, 268, 269, 275-288, 296-303, 309, 311-322, 324, 330, 331] and also very recent survey papers [42,60,61]) have extensively studied stability theorems for several kinds of functional equations in various spaces, for example, Banach spaces, 2-Banach spaces, Banach n-Lie algebras, quasi-Banach spaces, Banach ternary algebras, non-Archimedean normed and Banach spaces, metric and ultra metric spaces, Menger probabilistic normed spaces, probabilistic normed space, p-2-normed spaces, C -algebras, Cternary algebras, Banach ternary algebras, Banach modules, inner product spaces, Heisenberg groups and others. Further, we have to pay attention to applications of the Hyers-Ulam-Rassias stability problems, for example, (partial) differential equations, Fréchet functional equations, Riccati differential equations, Volterra integral equations, group and ring theory and some kinds of equations (see [66, 142, 150, 154, 159, 176, 185, 186, 192-194, 259-261, 327, 329]).…”