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François, Alexandre; Franjieh, Michael; Lacrampe, Sébastien; Schnell, Stefan (2015), "The exceptional linguistic density of Vanuatu" (PDF), in François, Alexandre; Lacrampe, Sébastien; Franjieh, Michael; Schnell, Stefan (eds.), The Languages of Vanuatu: Unity and Diversity, Studies in the Languages of Island Melanesia, Canberra: Asia Pacific Linguistics Open Access, pp. 1–21, ISBN9781922185235.