Kanchanathaweekul, T., and P. Muangmee. “Effects of Endurance Training and Breath-holding Training on Breath-holding Time, Maximal Oxygen Uptake, Lung Capacity, Red Blood Cell and White Blood Cell Counts”. Journal of Exercise and Sport Science, vol. 5, no. 1, Jan. 2008, pp. 1-16, https://he01.tci-thaijo.org/index.php/buuss/article/view/86724.