Moklyachuk, M. P., and M. M. Luz. “Minimax-Robust Estimation Problems for Sequences With Periodically Stationary Increments Observed With Noise”. Bulletin of Taras Shevchenko National University of Kyiv. Physics and Mathematics, no. 3 (November 30, 2020): 68–83. Accessed December 6, 2023. https://bphm.knu.ua/index.php/bphm/article/view/131.