Patel, P. A., J. S. Diwan, C. J. Shah, and H. B. Mehta. “Study of Heart Rate Variability in Hypertensive Subjects: Study of Heart Rate Variability in Hypertensive Subjects”. National Journal of Integrated Research in Medicine, vol. 6, no. 1, Feb. 2015, pp. 1-6, doi:10.70284/njirm.v6i1.845.