@article{GDZPPN00255092X,
title = {A sandwich theorem and Hyers-Ulam stability of affine functions.},
journal = {Aequationes mathematicae},
volume = {49},
year = {1995},
pages = {160-164},
zbl = {0815.39010},
url = {http://dml.mathdoc.fr/item/GDZPPN00255092X}
}
Nikodem, Kazimierz; Wasowicz, Szymon. A sandwich theorem and Hyers-Ulam stability of affine functions.. Aequationes mathematicae, Tome 49 (1995) pp. 160-164. http://gdmltest.u-ga.fr/item/GDZPPN00255092X/