@article{AM2_1977__15_136626,
     author = {Halina Swiatak},
     title = {On alternative functional equations.},
     journal = {Aequationes mathematicae},
     pages = {35--48},
     publisher = {mathdoc},
     volume = {15},
     year = {1977},
     zbl = {0348.39010},
     url = {http://geodesic.mathdoc.fr/item/AM2_1977__15_136626/}
}