[1]
P. DALKA, B. KOSTEK, and A. CZYŻEWSKI, “Vowel recognition based on acoustic and visual features”, Arch. Acoust., vol. 31, no. 3, pp. 275–288, Sep. 2006, Accessed: Apr. 18, 2026. [Online]. Available: http://acoustics.ippt.gov.pl/index.php/aa/article/view/673