[1]
E. I. Radzievskaya and G. V. Radzievskii, “Estimation of a K-Functional of Higher Order in Terms of a K-Functional of Lower Order”, Ukr. Mat. Zhurn., vol. 55, no. 11, pp. 1530–1540, Nov. 2003, Accessed: Dec. 05, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/4022