1. An integral of products of ultraspherical functions and a q-extension;Askey;J. London Math. Soc.,1986
2. Generalized translation operators associated with a singular differential operator;Braaksma,1974
3. Convolution and hypergroup structures associated with a class of Sturm–Liouville systems;Connett;Trans. Amer. Math. Soc.,1992
4. Sur une extension de la formule de Taylor;Delsarte;J. Math. Pure Appl.,1936