1. Akhiezer, N.I.: Lectures on the Theory of Approximation, 2nd edn. Nauka, Moscow (1965). (in Russian)
2. Bernstein, S.: Sur la meilleure approximation de $$\vert x\vert $$ par des polynômes des degrés donnés. Acta Math. 37, 1–57 (1913)
3. Bernstein, S.N.: Extremal Properties of Polynomials and the Best Approximation of Continuous Functions of a Single Real Variable. State United Scientific and Technical Publishing House, Moscow (1937). (in Russian)
4. Bernstein, S.: Sur la meilleure approximation de $$\vert x\vert ^p$$ par des polynômes des degrés trés élevés. Bull Acad. Sci. USSR Ser. Math. 2, 181–190 (1938)
5. Bernstein, S.N.: On the best approximation of continuous functions on the whole real axis by entire functions of given degree. V. Dokl. Akad. Nauk SSSR 54, 479–482 (1946). (in Russian)