Thomas, H., Murphy, M., Key, T., Fentiman, I., Allen, D., & Kinlen, L. (1998). Pregnancy and menstrual hormone levels in mothers of twins compared to mothers of singletons.
Chicago-viite (17. p.)Thomas, H., M. Murphy, T. Key, I. Fentiman, D. Allen, ja L. Kinlen. Pregnancy and Menstrual Hormone Levels in Mothers of Twins Compared to Mothers of Singletons. 1998.
MLA-viite (9. p.)Thomas, H., et al. Pregnancy and Menstrual Hormone Levels in Mothers of Twins Compared to Mothers of Singletons. 1998.
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