References
- Laver J. phonetic description of voice quality. Cambridge University Press. 1980
- Travis L. E. Handbook of Speech Pathology and Audiology. Appleton Century Crofts. 1971
- Wynter H. E. B.J.D.C. 1974; Vol. 9(No. 2)102–109
- Wynter H. E. An Investigation into the Analysis and Terminology of Voice Quality. B.J.D.C. 1974; Vol. 9(No. 2)102–109