1. The vowels and tones of Standard Thai: Acoustical measurements and experiments;Abramson;International Journal of American Linguistics,1962
2. The coarticulation of tones: An acoustic study of Thai;Abramson,1979
3. Fitting linear mixed-effects models using {lme4};Bates;Journal of Statistical Software,2015
4. Boersma, P., & Weenink, D. (2020). Praat: doing phonetics by computer [Computer program]. Version 6.1.16.
5. Articulatory coordination in word-initial clusters of German;Bombien;Journal of Phonetics,2013