https://www.cnet.com/news/amazon-blocks-book-that-tried-to-distribute-3d-printed-gun-blueprints/ > Amazon has removed a book that reproduced code for 3D-printed guns from its bookstore, saying the content violated its guidelines. > The 584-page book, called "The Liberator Code Book: An Exercise in Freedom of Speech," reprinted the code for Defense Distributed's plastic gun of the same name, according to The Washington Post. Defense Distributed is an Austin, Texas-based non-profit that researches and designs 3D-printable weapons.