Henning, E., H. Terblanche, M. Kleynhans, D. Crafford, P. Wood, C. Grant, and P. du Toit. “Comparing Cardio Stress Index Between Sedentary and Active Populations”. Suid-Afrikaans Tydskrif Vir Natuurwetenskap En Tegnologie / <i>South African Journal of Science and Technology</I&gt;, Vol. 33, no. 1, Sept. 2014, p. 1 bladsy, doi:10.4102/satnt.v33i1.1221.