Colin P. Groves. Department of Archaeology and Anthropology, The Australian National University, GPO Box 4, Canberra ACT 0200, Australia
Wilson, Don E., and DeeAnn M. Reeder, eds. 1992-01-01. Mammal Species of the World: A Taxonomic and Geographic Reference, 2nd ed., 3rd printing. Smithsonian Institution Press. Washington, DC, USA. xviii + 1207. 1-56098-217-9. Corrections were made to text at 3rd printing.
Wilson, Don E., and DeeAnn M. Reeder, eds. 2005-10-01. Mammal Species of the World: A Taxonomic and Geographic Reference, 3rd ed., vol. 1. Johns Hopkins University Press. Baltimore, Maryland, USA. xxxv + 743. 0-8018-8221-4. .
Mittermeier, Rusell A., Anthony B. Rylands, and Don E. Wilson, eds. 2013-01-01. Handbook of the Mammals of the World. Volume 3. Primates. Lynx Edicions. Barcelona, Spain. 951. 9788496553897. .
Wilson & Reeder, eds. (2005): Comments: Considered a subgenus of Presbytis by Szalay and Delson (1979); separated from Presbytis by Groves (1989). All taxa have generally been placed in a single species (entellus), but Groves (2001c) divided them into seven species