Kock, M.D.; Morkel, P.; Atkinson, M.W.; Foggin, C. 1995. Chemical immobilization of free-ranging white rhinoceros (Ceratotherium simum simum) in Hwange and Matobo National Parks, Zimbabwe, using combinations of Etorphine (M99), Fentanyl, Xylazine, and Detomidine. Journal of Zoo and Wildlife Medicine 26 (2): 207-219, figs. 1-2, table 1.