@article{AM2_1992__43_1_137444,
     author = {Ramon Badora},
     title = {On a joint generalization of {Cauchy's} and {d'Alembert's} functional equations.},
     journal = {Aequationes mathematicae},
     pages = {72--89},
     publisher = {mathdoc},
     volume = {43},
     number = {1},
     year = {1992},
     zbl = {0763.39003},
     url = {http://geodesic.mathdoc.fr/item/AM2_1992__43_1_137444/}
}