Classical 2-orthogonal polynomials and differential equations. Ammar, Boukhemis; Ebtissem, Zerouki — 2006 International Journal of Mathematics and Mathematical Sciences
On the 2-orthogonal polynomials and the generalized birth and death processes. Ebtissem, Zerouki; Ammar, Boukhemis — 2006 International Journal of Mathematics and Mathematical Sciences