|(690 cited 1981)|
Niuafoʻouan has traditionally been classified as closest to ʻUvean and Tokelauan, in an East Uvean–Niuafo'ou branch. Others suggest that it is closest to its neighbor, Tongan, as one of the Tongic languages. However, both groupings have been abandoned in the most recent classification, which did not include Niuafoʻouan.
- Niuafo'ou at Ethnologue (18th ed., 2015)
- Hammarström, Harald; Forkel, Robert; Haspelmath, Martin; Bank, Sebastian, eds. (2016). "Niuafo'ou". Glottolog 2.7. Jena: Max Planck Institute for the Science of Human History.
- Marck, Jeff (2000), Topics in Polynesian languages and culture history. Canberra: Pacific Linguistics.
- Austronesian Basic Vocabulary Database (2008)