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Susman, E.J. and Houts, R. and Steinberg, L. and Belsky, Jay and Cauffman, E. and Dehart, G. and Friedman, S.L. and Roisman, G.I. and Halpern-Felsher, B.L. (2010) Longitudinal development of secondary sexual characteristics in girls and boys between ages 9 1/2 and 15 1/2 Years. Archives of Paediatrics and Adolescent Medicine 164 (2), pp. 166-173. ISSN 1072-4710.