1. Characterization theorems for orthogonal polynomials;Al-Salam,1990
2. A generalisation of ultraspherical polynomials;Askey,1980
3. Formes linéaires et polynômes orthogonaux semi-classiques de class s = 1;Belmehdi,1990
4. On the associated orthogonal polynomials;Belmehdi;J. Comput. Appl. Math.,1990
5. Belmehdi, S. - Another characterization of the semi-classical orthogonal polynomials. Submitted.