Sûto's method applied to a problem of Färe and Mitchell
The author offers the general twice differentiable solution of the functional equation \[ \phi(x+\psi(y-x))=f(x)+g(y)+h(x)k(y) \] on a region in \(\mathbb{R}^ 2\). A seven row table is filled with solutions, even though they are just representatives of equivalence classes and the solutions in cases which have been known before are omitted. The problem takes its origin in mathematical economics.
scientific article; zbMATH DE number 92514