... tnorms In the sequel, we adopt the usual terminology, notations and conventions of the theory of random normed spaces, as in [35-37] Throughout this paper, Δ+ is the space of distribution functions, ... JM: On the stability of the non-linear Euler-Lagrange functional equation in real normed linear spaces J Math Phys Sci 28, 231–235 (1994) Rassias, JM: On the stability of the general Euler-Lagrange ... × Î X and all t > Hyers-ulam stability of the functional equation (1.4): an even mapping case In this section, we prove the Hyers-Ulam stability of the functional equation D f (x, y) = in complete...