Martínez-Celdrán, Eugenio; Fernández-Planas, Ana Ma.; Carrera-Sabaté, Josefina (2003), "Castilian Spanish", Journal of the International Phonetic Association, 33 (2): 255–259, doi:10.1017/S0025100303001373
Okada, Hideo (1991), "Phonetic Representation:Japanese", Journal of the International Phonetic Association, 21 (2): 94–97, doi:10.1017/S002510030000445X