Carbonell, Joan F.; Llisterri, Joaquim, Catalan, Journal of the International Phonetic Association, 1992,22 (1–2): 53–56,doi:10.1017/S0025100300004618
Cox, Felicity; Palethorpe, Sallyanne, Australian English, Journal of the International Phonetic Association, 2007,37 (3): 341–350,doi:10.1017/S0025100307003192
Cruz-Ferreira, Madalena, European Portuguese, Journal of the International Phonetic Association, 1995,25 (2): 90–94,doi:10.1017/S0025100300005223
Dankovičová, Jana, Czech, Handbook of the International Phonetic Association, Cambridge University Press: 70–74, 1999
Engstrand, Olle, Swedish, Handbook of the International Phonetic Association: A Guide to the usage of the International Phonetic Alphabet., Cambridge: Cambridge University Press: 140–142, 1999,ISBN 0-521-63751-1
Fougeron, Cecile; Smith, Caroline L, French, Journal of the International Phonetic Association, 1993,23 (2): 73–76,doi:10.1017/S0025100300004874
Gussenhoven, Carlos, Dutch, Journal of the International Phonetic Association, 1992,22 (2): 45–47,doi:10.1017/S002510030000459X
Hillenbrand, James M., American English: Southern Michigan, Journal of the International Phonetic Association, 2003,33 (1): 121–126,doi:10.1017/S0025100303001221
Ikekeonwu, Clara, Igbo, Handbook of the International Phonetic Association: 108–110, 1999,ISBN 0-521-63751-1
Jassem, Wiktor, Polish, Journal of the International Phonetic Association, 2003,33 (1): 103–107,doi:10.1017/S0025100303001191
Keating, Patricia A.,IPA Council votes against new IPA symbol, Journal of the International Phonetic Association, 2012,42 (2): 245 [2014-04-06],doi:10.1017/S0025100312000114, （原始内容存档于2012-11-11）,with only 15 of 30 members voting [by email], the vote was 8 in favor, 7 against. [...] With all 30 members of the Council voting [again six months later], the resolution was defeated: 17 no, 12 yes, 1 abstention. The IPA will therefore not be adding a symbol for this vowel to the alphabet or chart.
Labov, William; Ash, Sharon; Boberg, Charles, The Atlas of North American English, Berlin: Mouton-de Gruyter, 2006,ISBN 3-11-016746-8
Landau, Ernestina; Lončarića, Mijo; Horga, Damir; Škarić, Ivo, Croatian, Handbook of the International Phonetic Association: A guide to the use of the International Phonetic Alphabet, Cambridge: Cambridge University Press: 66–69, 1999,ISBN 0-521-65236-7
Lass, Roger, South African English, Mesthrie, Rajend (编), Language in South Africa, Cambridge University Press, 2002,ISBN 9780521791052
Laufer, Asher, Hebrew, Handbook of the International Phonetic Association: 96–99, 1999
Mangold, Max, Das Aussprachewörterbuch, Duden: 37, 2005,ISBN 9783411040667
Martínez-Celdrán, Eugenio; Fernández-Planas, Ana Ma.; Carrera-Sabaté, Josefina, Castilian Spanish, Journal of the International Phonetic Association, 2003,33 (2): 255–259,doi:10.1017/S0025100303001373
Rogers, Derek; d'Arcangeli, Luciana, Italian, Journal of the International Phonetic Association, 2004,34 (1): 117–121,doi:10.1017/S0025100304001628
Szende, Tamás, Hungarian, Journal of the International Phonetic Alphabet, 1994,24 (2): 91–94,doi:10.1017/S0025100300005090
Vanvik, Arne, Norsk fonetikk, Oslo: Universitetet i Oslo, 1979,ISBN 82-990584-0-6
Verhoeven, Jo, Belgian Standard Dutch, Journal of the International Phonetic Association, 2005,35 (2): 245,doi:10.1017/S0025100305002173
Wells, John C., Accents of English3, Cambridge University Press, 1982,ISBN 0-521-24225-8
Zimmer, Karl; Orgun, Orhan, Turkish, Handbook of the International Phonetic Association: A guide to the use of the International Phonetic Alphabet, Cambridge: Cambridge University Press: 154–158, 1999,ISBN 0-521-65236-7
Barry, William; Trouvain, Jürgen, Do we need a symbol for a central open vowel?, Journal of the International Phonetic Association, 2008,38 (3): 349–357
