@article{GDZPPN00202652X, title = {On Single-Product Functions with Rotational Symmetry.}, journal = {Aequationes mathematicae}, volume = {8}, year = {1972}, pages = {281-286}, zbl = {0261.39006}, url = {http://dml.mathdoc.fr/item/GDZPPN00202652X} }
Hall, R.L. On Single-Product Functions with Rotational Symmetry.. Aequationes mathematicae, Tome 8 (1972) pp. 281-286. http://gdmltest.u-ga.fr/item/GDZPPN00202652X/