[1]
S.M. Ulam, Some questions in analysis: 1, stability, Problems in Modern Mathematics, Science eds., Wiley, New York, 1964 (Chapter VI).
Google Scholar
[2]
D.H. Hyers, On the stability of the linear functional equation, Proc. Natl. Acad. Sci. USA 27 (1941) 222–224.
DOI: 10.1073/pnas.27.4.222
Google Scholar
[3]
Won-Gil Park, Jae-Hyeong Bae, On a Cauchy–Jensen functional equation and its stability, J. Math. Anal. Appl. 323 (2006) 634–643.
Google Scholar
[4]
V.A. Fa. ziev, T. Riedel, Stability of Jensen functional equation on semigroups, J. Math. Anal. Appl. 364 (2010) 341. 351.
Google Scholar
[5]
G.L. Forti, Hyers. Ulam stability of functional equations in several variables, Aequationes Math. 50 (1995) 143. 190.
DOI: 10.1007/bf01831117
Google Scholar
[6]
D.H. Hyers, G. Isac, Th.M. Rassias, Stability of Functional Equations in Several Variables, Progr. Nonlinear Differential Equations Appl., vol. 34, Birkhäuser Boston, Inc., Boston, MA, (1998).
DOI: 10.1007/978-1-4612-1790-9
Google Scholar