A method of manufacturing a physical medium configured to store data. A layout design of visible and invisible information to be printed in a book with visible and invisible ink, respectively, is generated. The visible information includes an article. The invisible information includes a URL of an address of a web server at which additional information associated with the article is located. Print data of the visible and invisible information based on the generated layout design of the visible and invisible information are generated. The generated print data of the visible and invisible information are stored on the physical medium. A book containing the article in visible ink and the invisible information in invisible ink is produced. A cellular phone is used to obtain the additional information by identifying the URL via illuminating and photographing the invisible information in the book using a light-emitting element in the cellular phone.