Procolobus verus is found on the western coast of Africa, from Sierra Leone to Tongo. There is also an isolated population in eastern Nigeria.
(Burton and Pearson, 1988; Oates and Whitesides, 1990; Flannery, 2000; Nowak, 1997)
Biogeographic Regions: ethiopian (Native )
- Burton, J., B. Pearson. 1988. The Collins Guide to the Rare Mammals fo the World. Lexington, Massachusetts: The Stephen Greene Press.
- Oates, J., G. Whitesides. 1990. Association between Olive Colobus, *Procolobus verus*, Diana guenons, *Cercopithecus diana*, and other Forest Monkeys in Sierra Leone.. American Journal of Primatology, 21/2: 129-146.
- Flannery, S. 2000. Accessed September 23, 2001 at www.primate.wisc.edu/pin/factsheets/procolobus_verus.html.
- Nowak, R. 1997. "Walker's Mammals of the World/Olive Colobus Monkey" (On-line). Accessed November 12, 2001 at www.press.jhu.edu/walkers_mammals_of_the_world/primates/primates.cercopithecidae.procolobus.html.