'So name some.'

Glad to!  
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Here's the American Psychological Association: http://www.apa.org/monitor/2013/04/biology.aspx
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Or the American College of Physicians:
https://www.acpeds.org/the-college-speaks/position-statements/gender-ideology-harms-children
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The Encyclopedia on Childhood development: http://www.child-encyclopedia.com/gender-early-socialization/introduction/does-biology-play-role-gender-development-and-behaviour
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Here's an article found right in this paper: http://www.theglobeandmail.com/life/science-in-transition-understanding-the-biology-behind-gender-identity/article25553156/

Note this phrase from the article: "The idea that male, female and transgender brains are different upsets feminists, for example, who maintain gender is a social construct." ... and it's in the G&M?  Wow.
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Or you could just Google "Nature vs. Nurture Gender" and take a gander at any of the hundreds of papers that get published every year on the topic. It's a pretty hot topic.