Hammarström, Harald (2018), "Language isolates in the New Guinea region", in Campbell, Lyle (ed.), Language Isolates, Routledge Language Family Series, Abingdon–New York: Routledge, pp. 287–322, doi:10.4324/9781315750026-11, ISBN978-1-317-61091-5, OCLC1000447105
Hammarström, Harald (2018), "Language isolates in the New Guinea region", in Campbell, Lyle (ed.), Language Isolates, Routledge Language Family Series, Abingdon–New York: Routledge, pp. 287–322, doi:10.4324/9781315750026-11, ISBN978-1-317-61091-5, OCLC1000447105