@article{10_4064_ap_6_3_281_287,
     author = {M. Kuczma},
     title = {On the functional equation {\ensuremath{\varphi}(x)+\ensuremath{\varphi}[f(x)]=F(x)}},
     journal = {Annales Polonici Mathematici},
     pages = {281--287},
     publisher = {mathdoc},
     volume = {6},
     number = {3},
     year = {1959},
     doi = {10.4064/ap-6-3-281-287},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap-6-3-281-287/}
}