Ahsan, M Farid, and MA Reza Khan. “Eco-Ethology of the Common Langur <i>Semnopithecus entellus< I> (Dufresne) in Bangladesh”. University Journal of Zoology, Rajshahi University, vol. 25, Aug. 2007, pp. 3-10, doi:10.3329/ujzru.v25i0.317.