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2. Über die konvergenz des Hermite-Fejérschen interpolationsverfahrens;Freud;Acta Math. Acad. Sci. Hungar.,1954
3. Orthogonal Polynomials;Freud,1971
4. On Hermite-Fejér interpolation processes;Freud;Studia Sci. Math. Hungar.,1972
5. On Hermite-Fejér interpolation sequences;Freud;Acta Math. Acad. Sci. Hungar.,1972