Jensen's functional equation on groups.
Jordan *-derivation pairs and quadratic functionals on modules over *-rings.
Jordan *-derivation pairs on a complex *-algebra.
Jordan *-derivation pairs on standard operator algebras and related results
Motivated by Problem 2 in [2], Jordan *-derivation pairs and n-Jordan *-mappings are studied. From the results on these mappings, an affirmative answer to Problem 2 in [2] is given when E = F in (1) or when 𝓐 is unital. For the general case, we prove that every Jordan *-derivation pair is automatically real-linear. Furthermore, a characterization of a non-normal prime *-ring under some mild assumptions and a representation theorem for quasi-quadratic functionals are provided.
Jordan homomorphisms in proper JCQ-triples.