Van Niekerk, Stephanie; Human, Stacey; Williams, June Heather; Van Wilpe, Erna; Pretorius, Marthi Andréa; Swanepoel, Robert; Venter, Marietjie(Centers for Disease Control & Prevention, 2015-12)
Adam, Ahmed; Engelbrecht, Matthys J.; Bornman, Maria S. (Riana); Manda, S.O.M. (Samuel); Moshokoa, Evelyn M.; Feilat, Rasmi A.(Wiley-Blackwell, 2011-04)