@article{AM2_1985__29_137075,
     author = {Konrad D. Heuvers},
     title = {A family of symmetric biadditive nonbilinear functions.},
     journal = {Aequationes mathematicae},
     pages = {14--18},
     publisher = {mathdoc},
     volume = {29},
     year = {1985},
     zbl = {0596.15026},
     url = {http://geodesic.mathdoc.fr/item/AM2_1985__29_137075/}
}