It's preferable to purchase GNU books and documentation through the FSF rather than Amazon: https://shop.fsf.org/books/signed-introduction-programming-emacs-li

It's preferable to purchase GNU books and documentation through the FSF rather than Amazon: https://shop.fsf.org/books/signed-introduction-programming-emacs-lisp-3rd-edition https://shop.fsf.org/books/signed-introduction-programming-e...