Christy, V. A., & Paton, J. G. (2002). Foundations in singing: A basic textbook in vocal technique and song interpretation (7th ed.). McGraw-Hill.
Chicago-viite (17. p.)Christy, Van Ambrose, ja John Glenn Paton. Foundations in Singing: A Basic Textbook in Vocal Technique and Song Interpretation. 7th ed. Boston: McGraw-Hill, 2002.
MLA-viite (9. p.)Christy, Van Ambrose, ja John Glenn Paton. Foundations in Singing: A Basic Textbook in Vocal Technique and Song Interpretation. 7th ed. McGraw-Hill, 2002.
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