Cox (2006) Cox, F.M. (2006), "The acoustic characteristics of /hVd/ vowels in the speech of some Australian teenagers", Australian Journal of Linguistics, 26: 147–179, doi:10.1080/07268600600885494Parameter |s2cid= yang tidak diketahui akan diabaikan (bantuan)
Durie & Hajek (1994) Durie, M.; Hajek, J. (1994), "A revised standard phonemic orthography for Australian English vowels", Australian Journal of Linguistics, 14 (1): 93–107, doi:10.1080/07268609408599503
Pearce (2011) Pearce, Mary (2011), "Kera", Journal of the International Phonetic Association, 41 (2): 249–258, doi:10.1017/S0025100311000168Parameter |s2cid= yang tidak diketahui akan diabaikan (bantuan)
Iivonen & Harnud (2005) Iivonen, Antti; Harnud, Huhe (2005), "Acoustical comparison of the monophthong systems in Finnish, Mongolian and Udmurt", Journal of the International Phonetic Association, 35 (1): 59–71, doi:10.1017/S002510030500191XParameter |s2cid= yang tidak diketahui akan diabaikan (bantuan)
Jassem (2003) The source transcribes this sound with the symbol ⟨ɨ⟩ but one can see from the vowel chart at pag. 105 that the Polish sound is closer to [ɘ] than to [ɨ]. Jassem, Wiktor (2003), "Polish", Journal of the International Phonetic Association, 33 (1): 103–107, doi:10.1017/S0025100303001191
Chirkova, Chen & Kocjančič Antolík (2013) Chirkova, Katia; Chen, Yiya; Kocjančič Antolík, Tanja (2013), "Xumi, Part 2: Upper Xumi, the Variety of the Upper Reaches of the Shuiluo River", Journal of the International Phonetic Association, 43 (3): 381–396, doi:10.1017/S0025100313000169
Chirkova & Chen (2013b) Chirkova, Katia; Chen, Yiya (2013b), "Xumi, Part 1: Lower Xumi, the Variety of the Lower and Middle Reaches of the Shuiluo River", Journal of the International Phonetic Association, 43 (3): 363–379, doi:10.1017/S0025100313000157
Kerr (1988) Kerr, Harland (1988), "Cotabato Manobo Grammar"(PDF), Studies in Philippine Linguistics, 7 (1): 1–123, diarsipkan dari versi asli(PDF) tanggal 2015-05-11Parameter |url-status= yang tidak diketahui akan diabaikan (bantuan)
Kerr (1988) Kerr, Harland (1988), "Cotabato Manobo Grammar"(PDF), Studies in Philippine Linguistics, 7 (1): 1–123, diarsipkan dari versi asli(PDF) tanggal 2015-05-11Parameter |url-status= yang tidak diketahui akan diabaikan (bantuan)