Standard Bulgarian, American Association of Teachers of Slavic and East European Languages: 42–54, 1958 Kristoffersen, Gjert, The Phonology of Norwegian
(2005:133–154頁) Bekker (2008:83–84頁) Case Studies – Received Pronunciation Phonology – RP Vowel Sounds. British Library. [2014-04-06]. (原始内容存档于2018-12-25)
sfnp error: no target: CITEREFBamgboṣe1969 (help) Árnason, Kristján, The Phonology of Icelandic and Faroese, Oxford University Press, 2011, ISBN 978-0-19-922931-4