@article{GDZPPN002022494,
title = {\"Uber die Funktionalgleichung f (1 + x) + f (1 + f (x)) = 1.},
journal = {Aequationes mathematicae},
volume = {1},
year = {1968},
pages = {267-274},
zbl = {0165.17201},
url = {http://dml.mathdoc.fr/item/GDZPPN002022494}
}
Benz, W.; Elliger, S. Über die Funktionalgleichung f (1 + x) + f (1 + f (x)) = 1.. Aequationes mathematicae, Tome 1 (1968) pp. 267-274. http://gdmltest.u-ga.fr/item/GDZPPN002022494/