Does anyone happen to know a good book or notes on intense field QED, for example about Volkov states and the Furry picture? To give you an idea of my pre-knowledge: I am a physics graduate student and I studied the first 6 chapters of the book by Peskin and Schroeder. I'm currently finishing up a course on QCD, so I am quite familiar with basic QED and QCD. I'm not (yet) so familiar with renormalization and functional methods, though I have seen some of it.