Boonruang Chunsuvimol. 1993. Relationship between the social variation of (r) in Thai and (r) in English in the speech of Bangkok Thai speakers. Graduate School, Chulalongkorn University;

Boonruang Chunsuvimol. Relationship between the social variation of (r) in Thai and (r) in English in the speech of Bangkok Thai speakers. . Bangkok:Chulalongkorn University, 1993.

Boonruang Chunsuvimol. (1993) Relationship between the social variation of (r) in Thai and (r) in English in the speech of Bangkok Thai speakers . Chulalongkorn University/Bangkok.