On the functional equation f(x + f(y)) = (x) f(y). (Short Communication). C.F.K. Jung; V. Boonyasombat — 1975 Aequationes mathematicae
On the functional equation f(x +f(y)) = f(x)f(y). C.F.K. Jung; V. Boonyasombat — 1976 Aequationes mathematicae