@article{AM2_1978__18_136765,
     author = {Marek Kuczma},
     title = {Functional equations on restricted domains.},
     journal = {Aequationes mathematicae},
     pages = {1--34},
     publisher = {mathdoc},
     volume = {18},
     year = {1978},
     zbl = {0386.39002},
     url = {http://geodesic.mathdoc.fr/item/AM2_1978__18_136765/}
}