“…In recent years, accompanied by the development of the Hyers–Ulam stability (also called Ulam–Hyers stability) of functional equations, e.g. , , , , –, many mathematicians paid attention to the problem of differential equations, for the papers concerning ordinary differential equations we refer the readers to , , , –, , , , . Further, the interested readers can see , , , , concerning the Hyers–Ulam stability of partial differential equations.…”