O'Hara, V. (1990). The fitness option: Five weeks to healing stress (2nd ed.). Dawn.
Chicago-viite (17. p.)O'Hara, Valerie. The Fitness Option: Five Weeks to Healing Stress. 2nd ed. Nevada City, CA: Dawn, 1990.
MLA-viite (9. p.)O'Hara, Valerie. The Fitness Option: Five Weeks to Healing Stress. 2nd ed. Dawn, 1990.
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