Zavhorodnia, V. A., S. O. Kovalenko, A. V. Rybalko, and S. I. Tokar. 2016. “The Influence of Respiration Upon the Oscillation Duration of R-R Interval and Cardiac Output”. Cherkasy University Bulletin: Biological Sciences Series, no. 1 (March):41-50. https://bio-ejournal.cdu.edu.ua/article/view/614.