↑Mikael Parkvall, "Världens 100 största språk 2007" (The World's 100 Largest Languages in 2007), in Nationalencyklopedin
↑Philippine Census, 2000. Table 11. Household Population by Ethnicity, Sex and Region: 2000
↑Hammarström, Harald; Forkel, Robert; Haspelmath, Martin; Bank, Sebastian, 편집. (2023). 〈Iloko〉. 《Glottolog 4.8》. Jena, Germany: Max Planck Institute for the Science of Human History.