Ulam Stability of Operators presents a modern, unified, and systematic approach to the field. Focusing on the stability of functional equations across single va

On becoming familiar with difference equations and their close re lation to differential equations, I was in hopes that the theory of difference equations could

This book is an outcome of two Conferences on Ulam Type Stability (CUTS) organized in 2016 (July 4-9, Cluj-Napoca, Romania) and in 2018 (October 8-13, 2018, Tim

Functional Equations, Inequalities and Applications provides an extensive study of several important equations and inequalities, useful in a number of problems

The notion of stability of functional equations of several variables in the sense used here had its origins more than half a century ago when S. Ulam posed the