[acbart]

You are correct that that is another large contributing factor. There are a few other ones too, such as the lack of real-world application of what they learn, stereotypes, a terrible culture towards women in CS, and a few other massive problems. They all work against the on-going efforts.

As for the Role Model aspect in particular... It's actually difficult to provide citations, because it's so commonly accepted in the community. I attended Grace Hopper '13 last year, and it's just recognized as a given. When I go through research papers from the past 5-10 years, they start off by just recognizing that its a known problem and then move onto subproblems or their new solution. Unfortunately, I don't really have the time to go mining the work that led to this problem being recognized. Still, I can recommend a book, "Unlocking the Clubhouse" http://mitpress.mit.edu/books/unlocking-clubhouse which should cover this!