1. Mean convergence of orthogonal series and Langrange interpolation;Askey;Acta Math. Acad. Sci. Hungar.,1972
2. Summability of Jacobi series;Askey;Trans. Amer. Math. Soc.,1973
3. A generalisation of ultraspherical polynomials;Askey,1980
4. S. Belmehdi, Formes linéaires et polynômes orthogonaux semi-classiques de classe s = 1. Description et classification, Thèse d'Etat, Université P. et M. Curie, Paris, 1990.
5. S. Belmehdi, On the left multiplication of a linear functional by a polynomial, in: C. Brezinski et al. (Eds.), IMACS Transactions on Orthogonal Polynomials and their Applications, IMACS Annals on Computing and Applied Mathematics, Basel, 1991, pp. 169–176.