... Rassias, On the stability of the linear mapping in Banach spaces,” Proceedings of the AmericanMathematical Society, vol. 72, no. 2, pp. 297–300, 1978.5 P. G˘avrut a, A generalization of ... M. Rassias, On the stability of functional equations and a problem of Ulam,” Acta ApplicandaeMathematicae, vol. 62, no. 1, pp. 23–130, 2000.16 Th. M. Rassias, Functional Equations, Inequalities ... Cauchy difference by a general control function in the spirit of Rassias’ approach.Rassias 6 during the 27th International Symposium on Functional Equations asked the question whether such a...