↑ 14,014,114,2Thomas (2004:308): A few younger speakers from, e.g., Texas, who show the Халип:Sc2/Халип:Sc2 merger have Халип:Sc2 shifted toward [a], but this retraction is not yet as common as in some non-Southern regions (e.g., California and Canada), though it is increasing in parts of the Midwest on the margins of the South (e.g., central Ohio).
Bolander, Maria (2001), Funktionell svensk grammatik (1st ред.), Liber AB, ISBN9789147050543
Collins, Beverley; Mees, Inger M. (2003) [First published 1981], The Phonetics of English and Dutch (5th ред.), Leiden: Brill Publishers, ISBN978-9004103405
Engstrand, Olle (1999), "Swedish", Handbook of the International Phonetic Association: A Guide to the usage of the International Phonetic Alphabet., Cambridge: Cambridge University Press, гь. 140–142, ISBN978-0-521-63751-0
Gilles, Peter; Trouvain, Jürgen (2013), "Luxembourgish", Journal of the International Phonetic Association, 43 (1): 67–74, doi:10.1017/S0025100312000278
Gordon, Matthew J. (2004), "The West and Midwest: phonology", Schneider, Edgar W.; Burridge, Kate; Kortmann, Bernd; Mesthrie, Rajend; Upton, Clive (ред-л.), A handbook of varieties of English, vol. 1: Phonology, Mouton de Gruyter, гь. 338–351, ISBN978-3-11-017532-5
Ikekeonwu, Clara (1999), "Igbo", Handbook of the International Phonetic Association, гь. 108–110, ISBN978-0-521-63751-0
Jassem, Wiktor (2003), "Polish", Journal of the International Phonetic Association, 33 (1): 103–107, doi:10.1017/S0025100303001191
Ladefoged, Peter (1999), "American English", Handbook of the International Phonetic Association (Cambridge Univ. Press): 41–44
Mokari, Payam Ghaffarvand; Werner, Stefan (2016), Dziubalska-Kolaczyk, Katarzyna (ред.), "An acoustic description of spectral and temporal characteristics of Azerbaijani vowels", Poznań Studies in Contemporary Linguistics, 52 (3), doi:10.1515/psicl-2016-0019
Rosenqvist, Håkan (2007), Uttalsboken: svenskt uttal i praktik och teori, Stockholm: Natur & Kultur, ISBN978-91-27-40645-2
Ternes, Elmer; Vladimirova-Buhtz, Tatjana (1999), "Bulgarian", Handbook of the International Phonetic Association, Cambridge University Press, гь. 55–57, ISBN978-0-521-63751-0
Thelwall, Robin; Sa'Adeddin, M. Akram (1990), "Arabic", Journal of the International Phonetic Association, 20 (2): 37–41, doi:10.1017/S0025100300004266
Thomas, Erik R. (2004), "Rural Southern white accents", Schneider, Edgar W.; Burridge, Kate; Kortmann, Bernd; Mesthrie, Rajend; Upton, Clive (ред-л.), A handbook of varieties of English, vol. 1: Phonology, Mouton de Gruyter, гь. 300–324, ISBN978-3-11-017532-5
Trudgill, Peter (2004), "The dialect of East Anglia: Phonology", Schneider, Edgar W.; Burridge, Kate; Kortmann, Bernd; Mesthrie, Rajend; Upton, Clive (ред-л.), A handbook of varieties of English, vol. 1: Phonology, Mouton de Gruyter, гь. 163–177, ISBN3-11-017532-0
Vanvik, Arne (1979), Norsk fonetikk, Oslo: Universitetet i Oslo, ISBN978-82-990584-0-7
Verhoeven, Jo (2007), "The Belgian Limburg dialect of Hamont", Journal of the International Phonetic Association, 37 (2): 219–225, doi:10.1017/S0025100307002940