Actually, Claudia Goldin's study (the 3rd link you posted and also the basis of the 2nd article) pretty much explains it all:
"What, then, is the cause of the remaining pay gap? Quite simply the gap exists because hours of work in many occupations are worth more when given at particular moments and when the hours are more continuous. That is, in many occupations earnings have a nonlinear relationship with respect to hours. A flexible schedule often comes at a high price, particularly in the corporate, financial, and legal worlds."
Men, on average, work longer hours than women, are more willing to have an inflexible schedule, and they are also significantly less likely to switch to part-time work (or drop out all together) when children are born, no matter what occupation they are in (hopefully you can read this link, but if not several articles above also explain much of the same, including Dr. Farrell's speech).
http://online.wsj.com/news/articles/SB10001424052702303592404577361883019414296
So in other words, even when you attempt to compare two people in the same occupation, you're still not comparing apples to apples. A male lawyer who is willing to work 80 hours a week with an inflexible schedule will not only obviously make more overall than a female lawyer who only works 40 and wants a flexible schedule, he's more likely to get promoted faster and get raises as well, thus leading to more average earnings.
Now, one could argue that the fact that women are more likely to drop out of the workforce or go part-time is the result of sexism and women expecting to maintain "traditional roles", and that would be a very legit point, but that is very different than out and out discrimination.