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Feinberg, D. R.; Jones, B. C.; Law Smith, M. J.; etal. (1 February 2006). "Menstrual cycle, trait estrogen level, and masculinity preferences in the human voice". Hormones and Behavior. 49 (2): 215–222. doi:10.1016/j.yhbeh.2005.07.004. PMID16055126. S2CID14884832.
Feinberg, D. R.; Jones, B. C.; Law Smith, M. J.; etal. (1 February 2006). "Menstrual cycle, trait estrogen level, and masculinity preferences in the human voice". Hormones and Behavior. 49 (2): 215–222. doi:10.1016/j.yhbeh.2005.07.004. PMID16055126. S2CID14884832.
Clutton-Brock, T. H.; Russell, A. F.; Sharpe, L. L. (2004). "Behavioural tactics of breeders in cooperative meerkats". Animal Behaviour. 68 (5): 1029–1040. doi:10.1016/j.anbehav.2003.10.024. S2CID53175143.
Shine, Richard; Langkilde, Tracy; Mason, Robert T. (2004). "Courtship tactics in garter snakes: How do a male's morphology and behaviour influence his mating success?". Animal Behaviour. 67 (3): 477–483. doi:10.1016/j.anbehav.2003.05.007. S2CID4830666.
Blouin-Demers, Gabriel; Gibbs, H. Lisle; Weatherhead, Patrick J. (2005). "Genetic evidence for sexual selection in black ratsnakes, Elaphe obsoleta". Animal Behaviour. 69 (1): 225–34. doi:10.1016/j.anbehav.2004.03.012. S2CID3907523.
Darwin, Charles (1859). On the Origin of Species (1st edition). Chapter 4, p. 88. "And this leads me to say a few words on what I call Sexual Selection. This depends ..." "Archived copy". Archived from the original on 2011-11-05. Retrieved 2011-05-22.{{cite web}}: CS1 maint: archived copy as title (link)