@article{MZ_1955__62_169507,
     author = {Fred Brafman},
     title = {Series of {Products} of {Gegenbauer} {Polynomials.}},
     journal = {Mathematische Zeitschrift},
     pages = {438--442},
     publisher = {mathdoc},
     volume = {62},
     year = {1955},
     zbl = {0065.05902},
     url = {http://geodesic.mathdoc.fr/item/MZ_1955__62_169507/}
}