Santandrea, S. 1953. "A Preliminary Account of the Indri, Togoyo, Feroge, Mangaya and Woro." In Sudan Notes and Records, XXXIV , no. 2: 230-264.
Sands, Bonny. 2005. "Juu Subgroups Based On Phonological Patterns." In Khoisan Language and Linguistics: the Riezlern Symposium 2003, edited by M. Brenzinger and C. König. 17: to appear. Köln: Rüdiger Köppe.