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半閉前不圓唇元音 Cambridge: Cambridge University Press, 1966 Basbøll, Hans, The Phonology of Danish , 2005, ISBN 0-203-97876-5 Carbonell, Joan F.; Llisterri, Joaquim
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半閉後圓唇元音 Cambridge: Cambridge University Press, 1966 Basbøll, Hans, The Phonology of Danish , 2005, ISBN 0-203-97876-5 Carbonell, Joan F.; Llisterri, Joaquim
清齦腭塞擦音Advanced Studies, 1959, ISBN 1-85500-055-5 (爱尔兰语) Wheeler, Max W., The Phonology of Catalan, Oxford: Oxford University Press, 2005, ISBN 0-19-925814-7