Attributes / relations provided by
♦ ¹Food Selection by the South Indian Leaf-Monkey, Presbytis johnii, in Relation to Leaf Chemistry, John F, Oates, Peter G. Waterman and Gillian M. Choo, Oecologia (Berl.) 45, 45-56 (1980)
♦ ²del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.