1. Leçons sur les propriétés extrémales et la meilleure approximation des fonctions analytiques d'une variable réelle;Bernstein,1926
2. Theory of approximation of functions, Macmillan;Timan,1963
3. Teoriya priblizheniya funktsii deistvitel′nogo peremennogo;Timan,1960
4. Weighted approximation on the real axis;Akutovicz;Jber. Deutsch. Math.-Verein,1966
5. On the approximation of continuous functions by polynomials on (∞, ∞) and (0, ∞) in terms of exponential weight factor;Cheng,1966