Kofanov, V. 2025. Boyanov–Naidenov problem and the Kolmogorov-type inequalities for functions on the real axis. Ukrains’kyi Matematychnyi Zhurnal. 77, 1 (Oct. 2025), 14–27. DOI:https://doi.org/10.3842/umzh.v77i1.8538.