Hyperstability of Generalised Linear Functional Equations in Several Variables

Zhang [‘On hyperstability of generalised linear functional equations in several variables’, Bull. Aust. Math. Soc. 92 (2015), 259–267] proved a hyperstability result for generalised linear functional equations in several variables by using Brzdęk’s fixed point theorem. We complete and extend Zhang’s result. We illustrate our results for general linear equations in two variables and Fréchet equations.