Earlier quoted context omitted.
The very exact text you are citing has links that lead to sources. Why would you ignore them?
OK, I see now. I was expecting citations in the usual academic-paper form as they were in other parts of the document. Didn't notice they were inline links. My bad. Thanks for correcting me.
If you are a bit interested in more references (those claims sound horrible, but they are not as far-fetched as they sound), have a look at https://www.youtube.com/watch?v=n691pLhQBkw. It's a presentation by Steven Pinker that explains a lot about what science actually has to say about biological differences, and in an aside at the end even mentions stereotypes.
I already mentioned it in a subthread to this post, no harm intended.