Table of contents : Front Matter....Pages i-vii Prologue....Pages 1-10 Introduction....Pages 11-14 Approximately Additive and Approximately Linear Mappings....Pages 15-44 Stability of the Quadratic Functional Equation....Pages 45-77 Generalizations. The Method of Invariant Means....Pages 78-101 Approximately Multiplicative Mappings. Superstability....Pages 102-131 The Stability of Functional Equations for Trigonometric and Similar Functions....Pages 132-154 Functions with Bounded n th Differences....Pages 155-165 Approximately Convex Functions....Pages 166-179 Stability of the Generalized Orthogonality Functional Equation....Pages 180-203 Stability and Set-Valued Functions....Pages 204-231 Stability of Stationary and Minimum Points....Pages 232-245 Functional Congruences....Pages 246-276 Quasi-Additive Functions and Related Topics....Pages 277-289 Back Matter....Pages 290-318