@article{GDZPPN002035243, title = {The general solution of a functional equation in two variables.}, journal = {Aequationes mathematicae}, volume = {28}, year = {1985}, pages = {7-13}, zbl = {0593.39007}, url = {http://dml.mathdoc.fr/item/GDZPPN002035243} }
Forti, Gian Luigi. The general solution of a functional equation in two variables.. Aequationes mathematicae, Tome 28 (1985) pp. 7-13. http://gdmltest.u-ga.fr/item/GDZPPN002035243/