Harrington, Cox & Evans (1997) Harrington, J.; Cox, F.; Evans, Z. (1997). "An acoustic phonetic study of broad, general, and cultivated Australian English vowels". Australian Journal of Linguistics. 17: 155–84. doi:10.1080/07268609708599550.
>Roach (2004:241–243), m.s. 21–22, 25–26. Roach memerhatikan bahawa banyak orang di England menggunakan /ɔː/ untuk vokal ini, tetapi juga bahawa RP dikatakan membezakan antara maw /mɔː/ dan moor /mʊə/, tore /tɔː/ dan tour /tʊə/, paw /pɔː/ dan poor /pʊə/. Roach, Peter (2004), "British English: Received Pronunciation", Journal of the International Phonetic Association, 34 (2): 239–245, doi:10.1017/S0025100304001768
