On linearization coefficients of Jacobi polynomials. - Hamza Chaggara; Wolfram Koepf (Appl. Math. Lett., 2010)

On linearization and connection coefficients for generalized Hermite polynomials. - Hamza Chaggara; Wolfram Koepf (J. Comput. Appl. Math., 2011)

Classification of 2-orthogonal polynomials with Brenke type generating functions. - Hamza Chaggara; Abdelhamid Gahami (J. Approx. Theory, 2025)