Throughout this text, there are references to links on the World Wide Web. As anyone who has tried to use the Web knows, these links can be highly unstable. I have tried to remedy the instability by redirecting readers to the original source through the Web site associated with this book. For each link below, you can go to http://free-culture.cc/notes and locate the original source by clicking on the number after the # sign. If the original link remains alive, you will be redirected to that link. If the original link has disappeared, you will be redirected to an appropriate reference for the material.