1. VARSE: VARvi Second Edition, https://milegroup.github.io/varse, modified: June 2019 (accessed: Sep. 2021).
2. VARSE: VARvi Second Edition, https://play.google.com/store/apps/details?id=com.devbaltasarq.varse, modified: September 2021 (ver. 1.6.9).
3. D. Dubin, Rapid interpretation of EKG’s: an interactive course, Cover Publishing Company, 2000.
4. The complete guide to ECGs;O’Keefe,2017
5. Power spectrum analysis of heart rate fluctuation: a quantitative probe of beat-to-beat cardiovascular control;Akselrod;Science,1981