The functional inequality is investigated, where is a group divisible by and are mappings, and is a Banach space. The main result of the paper states that the assumptions above together with (1) and (2) , or , imply that is additive. In addition, some stability theorems are proved.
"Functional Inequalities Associated with Additive Mappings." Abstr. Appl. Anal. 2008 1 - 11, 2008. https://doi.org/10.1155/2008/136592