Solution of the Ulam Stability Problem for Euler–Lagrange Quadratic Mappings

On approximation of approximately linear mappings by linear mappings

John Michael Rassias · Journal of Functional Analysis · 1982 · 574 citations

Natural Sciences, Computer Science, Mathematics +10

Hyers-Ulam stability of functional equations in several variables

Gian Luigi Forti · Aequationes Mathematicae · 1995 · 457 citations

Natural Sciences, Mathematics, Differential Equations +12

Solution of a problem of Ulam

John Michael Rassias · Journal of Approximation Theory · 1989 · 321 citations

Natural Sciences, Mathematics, Applied Mathematics +2

ON THE STABILITY OF THE GENERAL EULER-LAGRANGE FUNCTIONAL EQUATION

John Michael Rassias · Demonstratio Mathematica · 1996 · 58 citations · Full text

Natural Sciences, Mathematics, Differential Equations +12