@article{03781741, title = {The solution of the functional equation of d'Alembert's type for commutative groups.}, journal = {International Journal of Mathematics and Mathematical Sciences}, volume = {5}, year = {1982}, pages = {315-335}, doi = {10.1155/S0161171282000301}, zbl = {0496.39003}, language = {en}, url = {http://dml.mathdoc.fr/item/03781741} }
Rukhin, A.L. The solution of the functional equation of d'Alembert's type for commutative groups.. International Journal of Mathematics and Mathematical Sciences, Tome 5 (1982) pp. 315-335. doi : 10.1155/S0161171282000301. http://gdmltest.u-ga.fr/item/03781741/