@article{GDZPPN002029243,
title = {On the functional equation f(x +f(y)) = f(x)f(y).},
journal = {Aequationes mathematicae},
volume = {14},
year = {1976},
pages = {41-48},
zbl = {0322.39021},
url = {http://dml.mathdoc.fr/item/GDZPPN002029243}
}
Jung, C.F.K.; Boonyasombat, V. On the functional equation f(x +f(y)) = f(x)f(y).. Aequationes mathematicae, Tome 14 (1976) pp. 41-48. http://gdmltest.u-ga.fr/item/GDZPPN002029243/