DING H, HOFFMANN R, JOKISCH O. An Investigation of Tone Perception and Production in German Learners of Mandarin. Arch. Acoust. [Internet]. 2011 Sep. 30 [cited 2026 Mar. 4];36(3):509–518. Available from: https://acoustics.ippt.gov.pl/index.php/aa/article/view/161