A functional equation connected with the sine addition theorem Haruki, Hiroshi — 1976 Portugaliae mathematica
A generalization of Hille's and Robinson's functional equations Haruki, Hiroshi — 1981 Portugaliae mathematica
A new analogue of Gauss' functional equation. Haruki, Hiroshi; Rassias, Themistocles M. — 1995 International Journal of Mathematics and Mathematical Sciences
New generalizations of the Poisson kernel. Haruki, Hiroshi; Rassias, Themistocles M. — 1997 Journal of Applied Mathematics and Stochastic Analysis
On the Functional Equation f (x + t, y) + f (x - t, y) = f (x, y + t) + f (x, y - t). Hiroshi Haruki — 1970 Aequationes mathematicae
On an Application of the 'Square' Functional Equation to a Geometrie Characterization of Quadratic Functions from the Standpoint of Conformal-Mapping Properties HIROSHI HARUKI — 1971 Aequationes mathematicae
On an Application of the 'Square' Functional Equation to a Geometric Characterization of Quadratic Functions form the Standpoint of Conformal-Mapping Properties. (Short Communication). Hiroshi Haruki — 1970 Aequationes mathematicae
On a functional equation for Jacobi's elliptic function cn(z; k). Hiroshi Haruki — 1984 Aequationes mathematicae
A new functional equation characterizing generalized Joukowski transformations. Hiroshi Haruki — 1987 Aequationes mathematicae
On a generalization of Hille's functional equation Hiroshi Haruki — 1979 Annales Polonici Mathematici
On the equivalence of Hille's and Robinson's functional equations Hiroshi Haruki — 1973 Annales Polonici Mathematici
A functional equation arising from the Joukowski transformation Hiroshi Haruki — 1985 Annales Polonici Mathematici
On entire functions which transform straight lines into parabolas Hiroshi Haruki — 1975 Colloquium Mathematicae