Adhana, R., M. Agarwal, R. Gupta, and J. Dvivedi. “Effect of Slow Breathing Training on Heart Rate, Spontaneous Respiratory Rate and Pattern of Breathing”. International Journal of Research in Medical Sciences, vol. 4, no. 4, Dec. 2016, pp. 1027-30, doi:10.18203/2320-6012.ijrms20160724.