@article{10_1017_S204061850003433X,
     author = {Carlitz, L.},
     title = {The product of two ultraspherical polynomials},
     journal = {Glasgow mathematical journal},
     pages = {76--79},
     year = {1961},
     volume = {5},
     number = {2},
     doi = {10.1017/S204061850003433X},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S204061850003433X/}
}