1. Aronson, A. E. (1980). Clinical voice disorders, an interdisciplinary approach. New York: B.C. Decker.
2. Askenfelt, A. G., & Hammarberg, B. (1986). Speech waveform perturbation analysis: A perceptual-acoustical comparison of seven measures. Journal of Speech, Language, and Hearing Research, 29(1), 50–64.
3. Austin, D. (2008). The theory and practice of vocal psychotherapy: Songs of the self. London: Jessica Kingsley Publishers.
4. Baken, R. J., & Orlikoff, R. F. (2000). Clinical measurement of speech and voice. Boston: Cengage Learning.
5. Bernstein, D., & Fink, L. (1998). Manual for the childhood trauma questionnaire. New York, NY: The Psychological Corporation.