@article{GDZPPN002025078,
title = {A Proof of theEquivalence of the Equation f(x+y-xy)+f(xy) = f(x) + (y) and Jensen's Functional Equa tion},
journal = {Aequationes mathematicae},
volume = {7},
year = {1971},
pages = {24-29},
zbl = {0214.39102},
url = {http://dml.mathdoc.fr/item/GDZPPN002025078}
}
SWIATAK, HALINA. A Proof of theEquivalence of the Equation f(x+y-xy)+f(xy) = f(x) + (y) and Jensen's Functional Equa tion. Aequationes mathematicae, Tome 7 (1971) pp. 24-29. http://gdmltest.u-ga.fr/item/GDZPPN002025078/