On some special iteration groups
On stability of a functional equation connected with the Reynolds operator.
On stability of additive mappings.
On stability of the Cauchy equation on semigroups.
On subaddidive and Ψ-additive mappings
On subadditive functions and ψ-additive mappings
In [4], assuming among others subadditivity and submultiplicavity of a function ψ: [0, ∞)→[0, ∞), the authors proved a Hyers-Ulam type stability theorem for “ψ-additive” mappings of a normed space into a normed space. In this note we show that the assumed conditions of the function ψ imply that ψ=0 and, consequently, every “ψ-additive” mapping must be additive
On sums of dependent uniformly distributed random variables.
We study and solve several functional equations which yield necessary and sufficient conditions for the sum of two uniformly distributed random variables to be uniformly distributed.
On systems of linear functional equations.
On Tabor's problem concerning a certain quasi-ordering of iterative roots of functions.
On the abstract Hahn-Banach theorem due to Rodé.
On the Aleksandrov-Rassias problem and the Hyers-Ulam-Rassias stability problem.
On the asymptoticity aspect of Hyers-Ulam stability of quadratic mappings.
On the Bavrin integro-differential operators and their applications to the solution of functional equations.
On the Baxter functional equation.
On the Baxter functional equation. (Summary).
On the Beurling-Ahlfors functional inequality
On the Cauchy difference.
On the Cauchy equation modulo Z
On the Cauchy functional inequality in Banach modules.
On the characterization of quasiarithmetic means with weight function.