A Cohen-type inequality for Jacobi-Sobolev expansions. Fejzullahu, Bujar Xh. — 2007 Journal of Inequalities and Applications [electronic only]
A Cohen type inequality for Fourier expansions of orthogonal polynomials with a nondiscrete Jacobi-Sobolev inner product. Fejzullahu, Bujar Xh.; Marcellán, Francisco — 2010 Journal of Inequalities and Applications [electronic only]
Jacobi-Sobolev orthogonal polynomials: asymptotics for N -coherence of measures. Fejzullahu, Bujar Xh.; Marcellán, Francisco — 2011 Journal of Inequalities and Applications [electronic only]