Rangelov, Tihomir. 2019. The bilabial trills of Ahamb (Vanuatu): Acoustic and articulatory properties. In S. Calhoun, P. Escudero, M. Tabain and P. Warren (eds),Proceedings of the 19th International Congress of Phonetic Sciences, Melbourne, Australia 2019. Canberra, Australasian Speech Science and Technology Association Inc.: 1292-1296.
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See pp.33-34 of: Barbour, Julie (2012). A Grammar of Neverver. Germany: Mouton de Gruyter. ISBN9783110289619.