Ivanov, A. F., et al. “To the Bright Memory of Oleksandr Mykolayovych Sharkovsky. Sixty Years of the Famous Sharkovsky’s Theorem”. Ukrains’kyi Matematychnyi Zhurnal, vol. 76, no. 1, Feb. 2024, pp. 3-4, https://doi.org/10.3842/umzh.v76i1.8138.