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Anderson SE, Dallal GE, Must A (April 2003). „Relative weight and race influence average age at menarche: results from two nationally representative surveys of US girls studied 25 years apart”. Pediatrics111 (4 Pt 1): 844-50. DOI:10.1542/peds.111.4.844. PMID12671122.
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Hamilton-Fairley, Diana. Obstetrics and Gynaecology (Second izd.). Blackwell Publishing. Arhivirano iz originala na datum 2018-10-09. Pristupljeno 2015-05-09.