Abstract
In this article, we obtain a characterizations and representations of set-valued solutions defined on an Abelian group G with values in a Hausdorff topological vector space of the following generalized bi-quadratic functional equation:
for some nonnegative real numbers a, b, c, and d.
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EL-Fassi, Ii., El-Hady, ES. & Nikodem, K. On Set-Valued Solutions of a Generalized Bi-quadratic Functional Equation. Results Math 75, 89 (2020). https://doi.org/10.1007/s00025-020-01225-0
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DOI: https://doi.org/10.1007/s00025-020-01225-0