@article{AM2_1972__8_136302,
     author = {R.L. Hall},
     title = {On {Single-Product} {Functions} with {Rotational} {Symmetry.}},
     journal = {Aequationes mathematicae},
     pages = {281--286},
     publisher = {mathdoc},
     volume = {8},
     year = {1972},
     zbl = {0261.39006},
     url = {http://geodesic.mathdoc.fr/item/AM2_1972__8_136302/}
}