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

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

No books dealing with a comprehensive illustration of the fast developing field of nonlinear analysis had been published for the mathematicians interested in th

This book outlines the modern theory of functional equations and inequalities in several variables. It consists of three parts. The first is devoted to additive

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