DING H, HOFFMANN R, JOKISCH O. An Investigation of Tone Perception and Production in German Learners of Mandarin. Arch. Acoust. [Internet]. 2013 Oct. 25 [cited 2025 Apr. 25];36(3):509–518. Available from: https://acoustics3.ippt.pan.pl/index.php/aa/article/view/161