Bonin, C. (2021). Singing makes you happy: 10-minute workout for a beautiful voice. Self-Published.
Chicago-viite (17. p.)Bonin, Christin. Singing Makes You Happy: 10-minute Workout for a Beautiful Voice. [Place of publication not identified]: Self-Published, 2021.
MLA-viite (9. p.)Bonin, Christin. Singing Makes You Happy: 10-minute Workout for a Beautiful Voice. Self-Published, 2021.
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