1. A note on the precision of interpolation by Hermite-Fejér polynomials;Bojanic,1972
2. The Approximation of Continuous Functions by Positive Linear Operators;DeVore,1972
3. Ueber Interpolation;Fejér;Nachr. Akad. Wiss. Göttingen Math.-Phys. Kl.,1916
4. The Theory of Approximation;Jackson,1930
5. Remarks on the rapidity of convergence of Lagrange Interpolation;Kis;Ann. Univ. Sci. Budapest,1968