Grigoryan AL. Estimate of the Remainder of the Best Quadratic Approximation of Differentiable Functions by Polynomials. Ukr. Mat. Zhurn. [Internet]. 2004Dec.25 [cited 2024Nov.25];56(12):1691-8. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/3876