Endangered Languages Catalogue Project. Compiled By Research Teams At University of Hawai'i Mānoa and Eastern Michigan University . (2015) ·

Language isolates in the New Guinea region . Harald Hammarström (2017) · In Language isolates edited by Lyle Campbell, Thomas Dougherty, and Alexander D. Smith · London: Routledge

Other Language Groups in the Gulf District and Adjacent Areas ( pp. 263-277 ) . Karl J. Franklin (1973) · In The Linguistic Situation in the Gulf District and Adjacent Areas, Papua New Guinea edited by Karl J. Franklin · Research School of Pacific and Asian Studies, Australian National University

The Central and Western Areas of the Trans-New Guinea Phylum: Central and Western Trans-New Guinea Phylum Languages ( pp. 345-460 ) . C. L. Voorhoeve (1975) · In New Guinea Area Languages and Language Study Vol 1: Papuan Languages and the New Guinea linguistic scene Pacific Linguistics: Series C · Vol. 38 · edited by Stephen A. Wurm · Canberra: Research School of Pacific and Asian Studies, Australian National University

Glottolog 2.3 . Hammarström, Harald & Forkel, Robert & Haspelmath, Martin & Nordhoff, Sebastian (2014) · http://glottolog.org

A tentative classification of the languages of the Mt. Bosavi region ( pp. 189-215 ) . Shaw, Daniel R. (1973) · In The linguistic situation in the Gulf District and Adjacent areas, Papua New Guinea Pacific Linguistics Series · Vol. C26 · edited by Karl J. Franklin · Research School of Pacific and Asian Studies, Australian National University

The Bogaia of the Muller ranges, Papua New Guinea . Shllitoe, Paul (1993) · University of Sydney

The Appearing and Disappearing World of the Bogaiya: A Corner of Papua New Guinea Cultural History ( pp. 399-407 ) . Andrew J. Strathern and Pamela J. Stewart (2010) · In A mosaic of languages and cultures: studies celebrating the career of Karl J. Franklin edited by Kenneth A. McElhanon and Ger Reesink · SIL International

Language Atlas of the Pacific Area . Stephen Wurm and Shirô Hattori (1981) · Pacific Linguistics: Series C · Vol. 66-67 · Canberra: Research School of Pacific and Asian Studies, Australian National University