Dave Grossman is probably the best authority on PTSD. You can find his lectures on youtube if you're on the fence. He has a unique perspective, as he speaks from first hand experience with all of these matters, instead of purely from academic theory. Refreshing for anyone who is a bit tired of academia. Your professors will either love it, or hate it, depending on their bias and background. So use wisely in research papers.
That being said, I don't agree with David Grossman on 100% of the content or details of his book, but he is the most accurate I've seen so far. I'd give him a 90-95%, which is astounding.