There is so much published material available on the web, in journals and magazines and in conference proceedings that it is impossible for anyone to read it all. I have tried to avoid simply including links to web sites that I have not read.

Rather, I only include links to published articles that I have read and to web sites where I have reviewed the material as both relevant to the book and of reasonable quality. I have mostly avoided links to web sites that are simply Powerpoint presentations. However, for some topics, these are the best that is currently available and so I have included them.