Alexander, Martynenko, Gianfranco Raimondi, and Nikita Budreiko. “Time Irreversibility and Complexity of Heart Rate Variability”. The Journal of V. N. Karazin Kharkiv National University, series "Medicine"0, no. 41 (February 23, 2021). Accessed April 26, 2024. https://periodicals.karazin.ua/medicine/article/view/16876.