V. F. Babenko, V. A. Kofanov, and S. A. Pichugov, “Approximation of sine-shaped functions by constants in the spaces $L_p,\; p < 1$”, Ukr. Mat. Zhurn., vol. 56, no. 6, pp. 745–762, Jun. 2004, Accessed: Dec. 06, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/3795