A method of manufacturing a physical medium configured to store data. A layout design of visible information to be printed with visible ink in a book is generated, the visible information including an article. A layout design of invisible information to be printed with invisible ink in a book is generated, the invisible information including a Universal Resource Locator (URL) of an address of a web server at which additional information is located, the URL being encoded in a code within the invisible information, the additional information being associated with the article.