(en) Ryohei Kagaya, A Classified vocabulary of the Lenje language, Tokyo, Institute for the Study of Languages and Cultures of Asia and Africa (ILCAA), , 141 p.
(pt) Armindo Nguna (dir.) et Osvaldo G. Faquir (dir.), « Cicopi », dans Padronização da ortografia de línguas Moçambicanas : Relatório do III Seminário, Maputo, Centro de Estudos Africanos (CEA), Universidade Eduardo Mondlane, , p. 212-224
(en) Bishop Smyth et John Matthews, A vocabulary with a short grammar of xiLenge, the language of the people commonly called Chopi, spoken on the east coast of Africa between the Limpopo River and Inhambane, London, Society for Promoting Christian Knowledge, , 44 p. (lire en ligne)