1. A short history of orthogonal polynomials in a Sobolev space I, the non-discrete case;Meijer;Nieuw Arch. Wisk. (4),1996
2. J.J. Moreno-Balcázar, Propiedades analíticas de los polinomios ortogonales de Sobolev, Doctoral Dissertation, Universidad de Almería, Spain, 1997.
3. Computing orthogonal polynomials in Sobolev spaces;Gautschi;Numer. Math.,1995
4. F. Marcellán, A. Ronveaux, Orthogonal polynomials and Sobolev inner products: a bibliography, Internal Report, Universidad Carlos III de Madrid, Spain, 2011.
5. On polynomials orthogonal with respect to certain Sobolev inner products;Iserles;J. Approx. Theory,1991