Schwitzer, C., Mittermeier, R.A., Rylands, A.B., Chiozza, F., Williamson, E.A., Macfie, E.J., Wallis, J. and Cotton, A. (toim.).: Primates in PerilThe World's 25 Most Endagered Primates. 2017. IUCN SSC Primate Specialist Group (PSG), International Primatological Society (IPS), Conservation International (CI), and Bristol Zoological Society, Arlington, VA.. Viitattu 13.12.2023.