1. Phonetic variation of the Shanghai dialect in urban districts in the past 100 years;Chen,1995
2. Sanpoirone uihan gugeo moeumchegyeui byeoni gochal (A dispersion account on the change of contemporary Korean vowel system);Cho;Ling. Association Korean J.,2005
3. The vowels of Cheju;Cho;Korean J. Ling.,2001
4. Korean Phonetics and Phonology;Cho,2016
5. Gradient merging of vowels in Barcelona Catalan under the influence of Spanish;Cortés,2009