G. A. K.  Marshall, ?Notes on the Hylobiinae (Col., Curc.)?, Annals and Magazine of Natural History, vol. (10) 9, pp. 341-355, 1932.

G. A. K.  Marshall, ?Notes on the Hylobiinae (Col., Curc.)?, Annals and Magazine of Natural History, vol. (10) 9, pp. 341-355, 1932.