... Proceedings of the National Academy of Sciences of the United States of America, vol. 27, pp. 222–224, 1941.3 T. Aoki, “On the stability of the linear transformation in Banach spaces,” Journal of ... Journal of the MathematicalSociety of Japan, vol. 2, pp. 64–66, 1950.4 D. G. Bourgin, “Classes of transformations and bordering transformations,” Bulletin of the AmericanMathematical Society, ... Variables,vol.3 4of Progress in Nonlinear Differential Equations and Their Applications, Birkh¨auser, Boston, Mass, USA, 1998.8 S M. Jung, Hyers-Ulam-Rassias Stability of Functional Equations in Mathematical Analysis,...